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ASEAN Resistance to Sovereignty ViolationInterests, Balancing and the Role of the Vanguard State$

Laura Southgate

Print publication date: 2019

Print ISBN-13: 9781529202205

Published to Policy Press Scholarship Online: January 2020

DOI: 10.1332/policypress/9781529202205.001.0001

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The Third Indochina War1

The Third Indochina War1

(p.71) 3 The Third Indochina War1
ASEAN Resistance to Sovereignty Violation

Laura Southgate

Policy Press

Abstract and Keywords

This chapter reviews the events of the Third Indochina War between 1978 and 1991. Analysis of recently declassified United States documents helps shed light on the informal alliance that developed between Thailand, China, the ASEAN states, the ousted Khmer Rouge, and to a lesser extent the United States, in an effort to contain Vietnamese and Soviet influence in Southeast Asia following Vietnam’s invasion of Cambodia in 1978. As a consequence of high interest convergence between Thailand and a designated external power, China, ASEAN was able to resist violations to the sovereignty of Thailand from a Soviet-backed Vietnam.

Keywords:   ASEAN, China, United States, Cambodia, Vietnam, Sovereignty

The Third Indochina War, also referred to as the Cambodia conflict, began on 25 December 1978, when between 150,000 and 220,000 Vietnamese troops invaded and occupied neighbouring Cambodia.2 Rooted in Sino-Soviet rivalry, the conflict was intrinsically a product of the Cold War regional environment. Following Vietnam’s invasion of Cambodia, Vietnamese troops also became involved in small cross-border operations in Thailand, which ‘on several occasions seemed on the verge of launching a punitive attack on that country’.3 However, Thailand was never subjected to a Vietnamese invasion. As a response to Vietnamese aggression, Thailand sought closer diplomatic relations with China, weapons from Washington, and expanded its armed forces by a third.

In recognition of Thailand’s role as front-line state, external powers such as China and the US, as well as regional countries belonging to ASEAN, promised to come to Thailand’s aid if attacked by Vietnam. Chinese leader Deng Xiaoping succinctly expressed Chinese and Southeast Asian state fears regarding Vietnam in a meeting with US President Jimmy Carter on 29 January 1979.4 During this meeting, Deng informed Carter that ‘Vietnam has become totally Soviet controlled. At least a majority of ASEAN countries assess this as an extremely grave matter … ASEAN countries are now in the front line’.5 Evidence derived through analysis of the Third Indochina War (1978–91) will be used to support the argument that following Vietnam’s invasion of Cambodia in 1978, an informal alliance developed between Thailand, China, the ASEAN states, the ousted Khmer Rouge, and to a lesser extent the US, in an effort to contain Vietnamese and Soviet influence in Southeast Asia.6 As a consequence of high interest convergence between Thailand and a designated external power, China, ASEAN was able to resist violations to the sovereignty of Thailand from a Soviet-backed Vietnam. As a front-line (p.72) state, Thailand can be described as the vanguard state, having the most compelling interests at stake during the Cambodia conflict.

Throughout 1978 to 1991, the ASEAN states successfully lobbied the UN to deny international recognition of Vietnam’s puppet regime in Cambodia. Despite this, ASEAN’s diplomatic efforts were not sufficient to secure the withdrawal of Vietnam from Cambodia. Evidence will be presented to show that the end of the conflict was brought about by events outside of ASEAN’s control: namely, normalization of relations between the Soviet Union and China prior to the end of the Cold War. As the vanguard state, Thailand was able to set the agenda of ASEAN to portray a united ASEAN front for Thailand’s Vietnam policy, to garner great power security commitments, and to actively seek and support a great power intervention in regional affairs. While Thailand (in its capacity as the ASEAN vanguard state) clearly had an important role to play in this process, an equally important factor explaining ASEAN resistance to sovereignty violation during this time-period resides in the role played by external actors, and China in particular. As will be shown, without this external power support, it is highly likely Thailand would have resigned itself to a Vietnamese fait accompli in Cambodia.

Analysis of the Third Indochina War will begin with an assessment of the regional environment in the period 1975–1978. This period was characterized by a degree of regional uncertainty and mixed interest convergence. External power interests converged over the threat posed by Soviet expansion in the region, and a hegemonic Vietnam. However, the ASEAN states were divided. Certain ASEAN states sought a reduction in external power influence in the region. Other ASEAN states sought enhanced relations with external powers such as China, to offset the Vietnamese threat. The chapter will then consider the 1978 invasion of Cambodia by Vietnam, the China-Vietnamese Border War of 1979, and the effect of Vietnam’s invasion on the ASEAN states and Thailand, with the latter emerging as the ASEAN vanguard state.

Analysis will then consider Thailand’s external relations after the Vietnamese invasion, a period characterized by an increase in interest convergence between Thailand and China. It will be argued that this interest convergence caused the formation of an alliance, which was a catalyst for success of ASEAN resistance to sovereignty violation from a Soviet-backed Vietnam. An assessment of the regional environment in the period 1980 to 1991 will highlight the events that led to a withdrawal of Vietnamese troops from Cambodia. The chapter will conclude with a theoretical assessment of the chapter’s findings, and (p.73) analysis of alternative theoretical explanations for Thailand’s resistance to sovereignty violation.

The Southeast Asian regional environment (1975–1978)

In 1975, communist power was consolidated in three Southeast Asian countries: Vietnam, Laos and Cambodia. In Vietnam, the North Vietnamese communists emerged victorious from their struggle with the US-backed South. In the period 1975–78, China gradually curtailed economic and military aid to Vietnam,7 while the Soviet Union cancelled all of Hanoi’s debt to Moscow, valued at US$450 million.8 The Soviets also promised long-term aid to Vietnam in a joint communiqué on 30 October 1975, committing themselves to assisting the Vietnamese next five-year plan from 1976–80 with an aid package totalling US$2.5 million.9 This had the effect of drawing the Vietnamese closer to the Soviet Union. Having consolidated their power, the Vietnamese attempted to secure a number of objectives. These included: a nonthreatening region; the prevention of an anti-communist front in Indochina; the elimination of US presence; and the limitation of superpower activity in the region.10 The Vietnamese communists had historically considered that an Indochinese Federation should exist in the region, to include Vietnam, Laos and Cambodia. Domination over Indochina ‘required the elimination of extraneous influences in Laos and Cambodia’.11

Vietnam began by seeking a ‘special relationship’ with these countries. According to this relationship, governments in the two capitals would not make a major decision without clearing it with Hanoi first, and any foreign influence would be eliminated’.12 A Vietnamese delegation was sent to the Laos capital Vientiane in July 1975. Before the delegation left the capital, the Vietnamese signed with Laos a Treaty of Friendship and Cooperation. This treaty laid the basis for political coordination between the two, and for Vietnam’s security role in Laos.13 Relations developed further in February 1976 following the foundation of the Laos People’s Democratic Republic. Officials from Laos headed a delegation to Hanoi, the outcome of which was the ‘unambiguous declaration that Laos fell under Vietnam’s sphere of influence’.14 This was supplemented in July 1977 with the signing of a 25-year Treaty of Friendship.

In Cambodia, General Lon Nol had ousted the King of Cambodia, Prince Norodom Sihanouk, from power during a US-backed coup (p.74) on 18 March 1970.15 This was shortly followed by the US invasion of Cambodia in May. Lon Nol was staunchly anti-Vietnamese, unlike Sihanouk, who sympathized with the North Vietnamese struggle against the West. Sihanouk allowed the Vietnamese communists sanctuary along the Vietnam-Cambodia border, and arms transit through the country’s ports.16 Following the coup, Sihanouk sought refuge in Beijing, where the Chinese and North Vietnamese urged that he lend his name to the communist Cambodian resistance group, the Khmer Rouge. This government in exile, named The Royal Government of National Union of Kampuchea (GRUNK), existed between 1970 and 1976. The anti-Vietnamese Khmer Rouge, led by Brother Number One Pol Pot, had been fighting against the Sihanouk regime since 1967. However, it was in the regime’s best interests to cooperate with Sihanouk and the North Vietnamese after the Prince’s exile. The revolutionary faction gained legitimacy in Cambodia by using the Prince’s name, attracting support from the peasantry who were devoted to Sihanouk.17 This helped the Khmer Rouge gain control over Cambodia. The alliance also benefited the North Vietnamese, who saw the government in exile as a resistance to US domination and as a means of maintaining Vietcong sanctuaries within Cambodia.

Between 1973 and 1975, the Khmer Rouge aimed a number of offensives at the Cambodian capital, Phnom Penh. A February 1973 attempt failed after the US launched a massive B-52 bombing raid around the capital.18 An offensive in the early months of 1974 also failed, although the Khmer Rouge ‘noose around the city was considerably tightened’.19 The Khmer Rouge final offensive for Cambodia began in January 1975, following the rejection of further military aid to Cambodia from the US government.20 By April, they had closed in on Phnom Penh. At this time Lon Nol left the country, and the US made the decision to evacuate. By 17 April, the Khmer Rouge had taken control of the state, renaming it Democratic Kampuchea.

The Soviet and Vietnamese threat

Both China and the US perceived Vietnam, backed by the Soviet Union, to be a regional threat. As the Vietnam War developed, China increasingly voiced its disapproval of North Vietnamese collaboration with the Soviet Union, which enhanced Chinese fears of a larger Soviet encirclement policy directed against China.21 The feeling amongst the (p.75) Chinese was that, ‘if Vietnam was not against Moscow, it was against China’.22 Vietnamese reliance on the Soviet Union, and an increase in Soviet-Vietnamese cooperation, led to a further deterioration in both the Sino-Soviet and Sino-Vietnamese relationships.23 From as early as 1969, China began to reassess its policy towards the US. By engaging in Sino-American rapprochement, China could use the US to balance the Soviet threat. At the same time, a newly-elected President Nixon was beginning a similar reassessment of the Sino-American relationship. US rapprochement with China would engage the latter in balancing the Soviet Union, and would help to reduce US presence in Vietnam.24

From 1973 onwards, it became apparent to the US that China viewed Moscow and Hanoi as key regional threats. US Secretary of State, Henry Kissinger, confirmed that China ‘wants four separate Indochinese states and not one state dominated by Hanoi. Because they could not be sure that this single state would not be under the influence of Moscow’.25 In 1975, Deng Xiaoping, Vice Premier of the State Council of the People’s Republic of China (PRC), informed Kissinger of China’s fears that ‘the Soviet Union will increase its influence in Vietnam and Laos’.26 Similarly, in 1978, Foreign Minister Huang Hua informed US National Security Advisor Dr Zbigniew Brzezinski that ‘the countries that are subjected to the Soviet threat must make serious efforts to resist the expansion of the Soviet Union’.27 China was especially concerned about Soviet influence over Vietnam. Foreign Minister Hua informed Secretary of State Cyrus Vance in 1978 that Vietnam’s ‘objective is regional hegemony, and it has hired itself out to the Soviet Union, while the Soviet Union has exploited the ambitions of Vietnam to realize its aggression’.28

The US had similar concerns, which were heightened following US retrenchment from Southeast Asia following the conclusion of the Vietnam War. In a meeting between Kissinger and Vice Premier Deng in 1974, Kissinger stated that the US ‘will not permit a strategic gain for Soviet power. We will attempt to reduce Soviet power where we can’.29 The US was similarly aware of Soviet influence over Vietnam, and the latter’s desire for regional hegemony. Dr Brzezinski informed Foreign Minister Hua in 1977 that the US is ‘opposed to the creation of an Indochinese federation dominated by Vietnam. We realize what is behind it’.30 US Secretary of Defence Harold Brown surmised that, ‘to the extent our opening to China reduces the chances of Sino-Soviet détente, we gain enormously … it is very important to stabilize our relationship with China and to avoid the situation where the Chinese are allied with the Soviets against us’.31

(p.76) Clearly, in the period 1975 to 1978, Chinese and US interests increasingly converged with respect to the Soviet and Vietnamese threat. Both China and the US believed that the Soviet Union had expansionist aims for Southeast Asia. Both states also recognized Vietnam’s potential hegemonic ambitions, which they believed were supported by the Soviet Union. For both China and the US, improved relations were seen as a vital component in balancing the Soviet Union, blocking its expansion further east and tying down a portion of the Soviet military effort.

Intra-ASEAN interest divergence

While threats posed by the Soviet Union and Vietnam led to increased interest convergence between China and the US, the ASEAN states were less able to reach a common threat consensus. This was despite Vietnamese communist victory and US regional retrenchment having a major impact on the region. The non-communist ASEAN states, which in 1975 included Indonesia, Malaysia, the Philippines, Singapore and Thailand had, to varying degrees, all relied upon the US security umbrella during the Vietnam War. Many of the ASEAN states provided diplomatic or military support to the US in its effort against the North Vietnamese. Most notable contributions involved Thailand, which assisted the US bombardment of North Vietnam and sent ground combat forces to support South Vietnam,32 and the Philippines, which maintained major US military bases on the island of Luzon.33 US retrenchment was therefore met with much regional consternation. This was especially notable in Thailand and the Philippines, which had provided most help to the US during the war. Regional states voiced their concerns during a visit made by Mr Habib to Southeast Asia in June 1975. In a memorandum from Kissinger to US President Gerald Ford summarizing the trip, Kissinger confirmed that for the Southeast Asian states ‘there is a uniform desire that the US play a supporting – and deterrent – role in the region’.34 Indonesian Foreign Minister Adam Malik expressed a similar view to Kissinger in 1976, stressing that the ASEAN states ‘regard as especially important that the US remain interested in Southeast Asia’.35

Following the Paris Peace negotiations, there was a move among the ASEAN states to establish diplomatic relations with North Vietnam. Malaysia established relations with Hanoi on 30 March 1973.36 This was followed by Singapore on 1 August 1973.37 Indonesia, which had established diplomatic relations with Hanoi in 1964, sent an (p.77) ambassador to North Vietnam in early 1973.38 While Thailand and the Philippines also made an attempt to establish diplomatic relations at this time, their collaboration with the US during the Vietnam War hampered these efforts. Thailand extended an invitation to the North Vietnamese to send an observer to the ASEAN Ministerial Meeting to be held in April 1973. Hanoi rejected this invitation due to Thai involvement in the Vietnam War. ASEAN extended a similar invitation in 1974. However, Hanoi argued that ASEAN was too heavily influenced by the West, and the Association was ‘venomously flayed as a de facto military alliance’.39

The suddenness with which the Vietnam War ended caused considerable alarm among the ASEAN states. However, the period is notable for the disparate ASEAN state responses to North Vietnamese victory. As one commentator noted, ‘much of the initiative towards accommodation with the emerging realities of the power structure in the region was effectively in the hands of individual member states rather than in ASEAN as a regional grouping’.40 The lack of ASEAN consensus was reflected in the Joint Communiqué issued at the end of the 8th ASEAN Ministerial Meeting on 13–15 May 1975, which made no mention of recent developments in Indochina.41 Of the ASEAN states, most alarm was felt in Thailand, ‘the country closest to the epicentre of political and military turmoil’.42 In a January 1975 meeting the Thai Foreign Minister, Charunphan Isarangkun Na Ayuthaya, stated that the Thai government was aware that if both Cambodia and South Vietnam collapsed to North Vietnam, the next major threat ‘first and foremost is Thailand’.43 In a June 1975 Secretary of State Staff meeting, Mr Habib confirmed that ‘the Thai are desperate to find some means of protecting themselves. So they will try every diplomatic channel … at the same time, they will be pleading, I am sure, with the ASEAN group to give them the support of the regional organisation’.44

By November 1975, a Thai strategy to counter the Vietnamese threat was already beginning to materialize. In a meeting between Secretary Kissinger and the Thai Foreign Minister Chatchai Chunawan, Kissinger informed Chatchai that the US would like Cambodia ‘to be independent as a counterweight to North Vietnam … we would prefer to have Laos and Cambodia aligned with China rather than with North Vietnam. We would try to encourage this if that is what you want’.45 Chatchai replied: ‘yes, we would like you to do that … the Chinese are 100 percent in support of Cambodia’s being friends with Thailand’. Chatchai informed Kissinger that he had ‘asked the Chinese to take over in Laos’. Kissinger stated that the US ‘would support (p.78) this. You should also tell the Cambodians that we will be friends with them. They are murderous thugs, but we won’t let that stand in our way’. Confirming this strategy in a separate meeting between Chatchai and New Zealand officials, Chatchai stated that he wanted Cambodia and Laos ‘strong enough to be buffers between Thailand and [the] Vietnamese’.46 Similarly, in a meeting with Japanese officials in Tokyo in October 1975, Chatchai made it clear that the situation in Indochina was ‘very dangerous’ for Thailand, and that Hanoi was the major threat.47 Japanese officials believed Chatchai implied a ‘linked PRC, Cambodia and Thailand in [a] quasi-alliance’.48

The remaining ASEAN states exhibited varying levels of concern, with Vietnamese communist victory bringing ‘the least response from the country furthest away, Indonesia’.49 Indonesian Minister of Defence General Maraden Panggabean stated in April 1975 that ‘naturally [the] prospect of communist takeover in Indochina creates a very real concern in Indonesia’.50 However, ‘Indonesians hoped … and were inclined to believe, that communists in Indochina were as much nationalists as communists. If this was [the] case, relations with them over longer term would be possible’.51 The Indonesian government also believed that this was a view shared by other ASEAN states. Indonesian Director-General of Political Affairs Djajadiningrat stated that the ASEAN states would welcome membership of a communist Vietnam in ASEAN, so long as the ‘Vietnamese regime is not expansionist and is willing to be [a] good neighbour’.52

The Malaysian government recognized the PRG [Provisional Revolutionary Government of the Republic of South Vietnam] following the fall of Saigon, stressing that good relations could exist with the Vietnamese communist government, whilst ‘privately fear[ing] the results of Indochina’s fall’.53 Taking a position similar to that of Indonesia, acting Malaysian Prime Minister, Ghafar Baba, stated the Malaysian hope that ‘both the new governments in Cambodia and South Vietnam would cooperate with ASEAN countries’.54 Singapore’s Prime Minister, Lee Kuan Yew, took an approach closer to that of Thailand. Lee informed Kissinger in a meeting in May 1975 that his ‘immediate reaction [to the fall of Saigon] is one of astonishment and alarm at the rapidity with which the situation fell apart’.55 Kissinger informed Lee that ‘this year Hanoi will do more than take Laos. They are fully occupied with absorbing what they have already conquered. They are very careful planners, and they will step up in Thailand and Malaysia next year’. Lee agreed, stating that the North Vietnamese ‘have American weapons now. It sends chills down my spine. My worst fears have come true … I must be careful so as (p.79) not to scare the Malays and the Thais that the situation is hopeless … Laos and Cambodia are gone’.

According to Lee, the North Vietnamese ‘need only take the corner of Thailand, and they could for example take over the Mekong hydroelectric scheme. They would then have the entire Mekong delta. That is one step they may risk. Then they would have a basis for becoming an industrial power.’ In an April 1975 meeting between Lee and a Thai delegation in Bangkok, that included the Thai Prime Minister Khukrit Pramot and Foreign Minister Chatchai, Lee informed Chatchai that he sees Thailand as potentially ‘the next domino’ in Southeast Asia.56 It was therefore vital that they maintain a US presence in order to resist communist incursions.57 Of all the ASEAN states, the Philippines remained the most detached from the crisis. Geographically isolated and home to US bases, the Philippines President Marcos remained ‘firm in his expressions that the US-Philippine security relationship is essential to his country’.58

Vietnam and the Soviets seek enhanced Southeast Asia relations

Meanwhile, seeking to enhance regional security and secure economic aid, a reunified Vietnam began to make diplomatic overtures towards the ASEAN states. These first began in 1976, when Hanoi announced a policy of establishing ‘relations of friendship and cooperation’ with Southeast Asian countries.59 Relations were to be based on a mutual respect for independence, good neighbour policies and the prevention of regional countries being used as a base for external power aggression. However, Vietnam would only deal with regional states individually, believing ASEAN to be a ‘product of the US imperialist policy of intervention and aggression’.60 Vietnam was forced to reassess this position in mid-1978, at a time of increased Sino-Vietnamese conflict. In competition with China for the ‘hearts and minds’ of ASEAN, Vietnam announced its willingness to deal with ASEAN in June 1978.61 In September 1978, Vietnam’s Prime Minister, Pham Van Dong, visited the capitals of ASEAN, dispensing assurances of non-intervention.62 Prime Minister Pham was particularly concerned with trying to obtain a friendship treaty with Thailand. Pham ‘dropped Hanoi’s demand for the return of all planes and vessels used by refugees fleeing South Vietnam in 1975, pledged that Vietnam would not support the Thai insurgency, signed agreements in repatriation of refugees who had fled Vietnam in the 1940s and on commercial and economic cooperation’.63 Vietnam’s Deputy Foreign Minister, Phan (p.80) Hien, also ‘recognized ASEAN as a “genuine regional organization for economic cooperation”’.64 All of the ASEAN states, despite varying policies towards Vietnam, decided against rushing into a formal agreement with Vietnam at that time.65

Following the end of the Vietnam War, the Soviet Union revived the notion of a collective security system in Asia, which it had been attempting to garner support for since as early as 1969. The Soviet aim was to take advantage of US disengagement, to increase a regional presence, and to assert influence against the Chinese.66 However, the proposal never received regional support. This was largely due to regional states recognizing the proposal as an anti-China move, and not wishing to provoke Beijing.67 The Soviet Union also sought to reconcile ASEAN and Vietnam in the hope that ‘the ASEAN countries might become more receptive to influence from the communist states in Indochina’.68 The Soviets particularly sought to capitalize on ASEAN efforts for a Zone of Peace, Freedom and Neutrality (ZOPFAN). ZOPFAN was identified as a regional goal by the ASEAN states at the 1971 Kuala Lumpur Declaration, and was in part a response to the intrusive Soviet collective security scheme.69 In this declaration, the ASEAN countries stated their intent to keep Southeast Asia free from external interference by outside powers. The Soviet Union seized upon ZOPFAN ‘as an indication that the region was moving away from total reliance upon the West’.70 While some ASEAN states did move to enhance diplomatic relations with the Soviet Union, this did not result in any formal alliances. Kissinger confirmed that the regional states ‘are all suspicious’ with regard to the Soviet Union, ‘they place their trust in the US deterrent and the Sino-Soviet conflict as the basic checks on soviet expansionism in Asia’.71

Thailand was willing to tolerate an increased regional role for the Soviet Union following the end of the Vietnam War. However, this was only as a means to maintain some regional US presence, and to demonstrate to Vietnam that Thailand was not completely dependent on the US or China.72 Soviet diplomatic relations with the Philippines was restored in June 1976. However, this was recognized by the Soviets as of secondary importance to relations with China, which had been restored in June 1975. While the Soviet Union hoped that shared perceptions of a threatening China might make Indonesia amenable to their influence, ‘Indonesian desire for the removal of the great powers from the region conflict[ed] with Soviet intentions’.73 Malaysia hoped that the Soviet Union might play a mediating role between Vietnam and the ASEAN states. However, Malaysian desire for a reduction in great power influence in the region meant that this was the extent to (p.81) which Soviet involvement was encouraged. Taking a similar approach to that of Thailand, Singapore engaged with the Soviet Union to maintain a regional balance of power, hoping Soviet engagement would act as a ‘device to ensure a continuing Western presence in the region’.74

ASEAN-China relations

During the 1949 to 1970 period, the states of Southeast Asia viewed China as having regional hegemonic intentions. Chinese-backed communist insurgencies in Southeast Asia had threatened domestic political structures and regional peace and stability. Indonesia suspected Beijing’s involvement in a 1965 communist conspiracy, which killed the large majority of Indonesia’s top military command.75 Chinese support for communist guerillas in Thailand and Malaysia also continued late into the 1970s.76 To balance this threat, the ASEAN states sought an enhanced US regional presence. However, this situation changed with US-Chinese rapprochement, US retrenchment following the Vietnam War, and an increase in Sino-Soviet and Sino-Vietnamese hostilities. At this time, the majority of the ASEAN states sought to normalize relations with China. Malaysia was first to establish relations with China in May 1974, followed by the Philippines in June 1975 and Thailand in July 1975. By late 1975, China had started to reduce its support for communist insurgencies in Southeast Asia. One US official noted that ‘Peking’s public views … have been muted of late. Particularly since the establishment of relations with Bangkok and Manila’.77 This was seen as an effort to ‘placate ASEAN governments’ sensitivity concerning public PRC support for the insurgents’.78 Singapore, although stating that it would not establish relations with China before Indonesia, still sought to improve its relations with Beijing.79 Lee informed US Secretary of Defence, James Schlesinger, in May 1975 that the North Vietnamese could move all the way to Singapore, and that Singaporeans ‘don’t believe the US would make a move, but we do believe the PRC would, and that is protecting us’.80

This left Indonesia ‘practically isolated’ from the rest of ASEAN.81 Indonesia traditionally viewed China as an, ‘aggressive and expansionist power,’ and was displeased with Beijing’s attempt to ‘woo’ ASEAN countries, and with the ‘current “panicky rush” of ASEAN countries to Beijing’.82 Deng Xiaoping told US President Ford in December 1975 that, ‘Indonesia does not have good relations with us, but we are in no hurry … as far as China is concerned, we are willing to improve (p.82) relations with Indonesia, but we have patience’.83 Ford informed Deng that he will ‘speak very forcefully to them concerning this effort’ when he is next in Indonesia.84

Of the ASEAN states, Thailand was most keen to develop diplomatic relations with China. In a May 1975 meeting Lee Kuan Yew informed Kissinger that Thailand would ‘come to terms with China … China is their insurance agent’.85 Thai Foreign Minister Charunphan confirmed this approach in a 1975 meeting with US Senators Thurmond and Scott, stating that ‘the Thai had been approaching China confidentially to lower the level of these [subversive] activities [in Thailand] since before President Nixon went to Peking’.86 US ambassador to Thailand, Charles Whitehouse, informed US National Security Advisor, Brent Scowcroft, that ‘the Thai saw Vietnam as the real threat and China as a rather benevolent power even if some Thai also recognized that this benevolence stemmed from China’s self-interest’.87 Enhanced relations resulting from the Vietnamese threat had an immediate impact on bilateral trade between Thailand and China, which increased from US$4.7 million in 1974 to US$136.4 million in 1976.88

China encourages enhanced Thai-Cambodian relations

China also mediated an agreement to establish relations between Thailand and Cambodia in 1975.89 This was a vital component in China’s Vietnamese containment policy. Historically, relations between Thailand and Cambodia had been characterized as one of ‘unending conflicts’.90 Cambodia viewed Thailand as an, ‘oppressive neighbour’ which sought to envelop Khmer territory.91 Despite this history of poor relations, Thailand recognized that Cambodia could be used as a ‘fence state’ to protect itself from Vietnamese attack.92 Thailand could also be useful to Cambodia. Democratic Kampuchea had already begun a diplomatic offensive with regard to the ASEAN states in 1975, recognizing ‘diplomatic support of ASEAN as an important factor given an impending conflagration’.93 Thai and Cambodian officials met twice in 1975, at China’s behest. At Thailand’s insistence, the ASEAN states ‘collectively and promptly recognized the new Phnom Penh government’ on 18 April 1975.94 In October 1975, Cambodian Foreign Minister, Ieng Sary, visited Bangkok, where it was agreed that Thailand and Cambodia would establish diplomatic relations.95

In an official scheduled visit by Chinese Vice-Premier Deng to Thailand, Malaysia and Singapore in early November 1978, Deng sought support for China’s Vietnam policy, and ‘impressed upon his (p.83) foreign hosts that China would use force against Vietnamese aggression if Vietnam attacked Cambodia’.96 Evidence therefore suggests that by 1978, at least two ASEAN states had adopted a clear policy that sought to engage with external powers to face the Vietnamese threat. The remaining ASEAN states believed that accommodation with the Vietnamese may be possible, and that engagement with external powers compromized a ZOPFAN in Southeast Asia. These different strategies prevented the formation of a united ASEAN front. Instead, the regional states largely pursued policies in defence of their own national interests.

Vietnam’s invasion of Cambodia – a catalyst for convergence

The Khmer people had long been wary of Vietnamese regional ambitions. According to Prince Sihanouk, ‘the Khmer people have serious reasons not to like the Vietnamese. Our neighbours in the east have, in effect, in the course of the centuries, “swallowed” territories which had always belonged to Cambodia’.97 In relations with Vietnam, Sihanouk stated that he ‘always adopted a realist attitude … it was a very dangerous neighbour, to be handled with care’.98 Sihanouk concluded that the US would eventually retrench from the Southeast Asian region, thus making accommodation with North Vietnam inevitable. Unlike Sihanouk, the Khmer Rouge did not wish to accommodate the Vietnamese due to Vietnam’s history of intervention in Cambodia, which had seen Khmer territory ceded to the Vietnamese. The opinion within the Khmer resistance government was that Vietnam was their ‘acute enemy’.99 Clashes between Khmer fighters and Vietnamese troops were reported throughout the mid-1970s. In an attempt to gain total control of Cambodia, the Pol Pot group ‘stepped up a campaign to denigrate Sihanouk’100 and sought to ‘blunt Vietnamese expansion, [and] pre-empt Hanoi’s effort to exert influence over Phnom Penh’.101 As Sihanouk’s role in Cambodia was increasingly marginalized, clashes between the Khmers and the Vietnamese communists escalated.102

The North Vietnamese tolerated these clashes in order to maintain sanctuaries along the Cambodia border. Similarly, while Cambodia wanted to avoid the emergence of a strong Vietnam in Indochina, the balance of forces within the Communist Party of Kampuchea (CPK) was not ready for open confrontation with the North Vietnamese.103 In 1976, Pol Pot argued that the building of communism in Democratic (p.84) Kampuchea had to be hurried, in order to confront the Vietnamese with greater strength.104 According to a research study prepared by the CIA, the Khmer Rouge communists showed themselves ‘to be the most extreme of the world’s totalitarian regimes’.105 The regime adopted ‘unorthodox economic practices’, that included the total mobilization of the Cambodian people, abolition of private ownership and the departure from a money economy.106 The Cambodian urban population underwent forced resettlement into rural areas, which was justified ‘as a means to create a huge permanent labour force in the countryside’.107 In its desire to implement a communist system quickly, it is believed 21 to 26 percent of the country’s population were killed.108 Even those within the regime were subject to large-scale killings and routine purges.109

The Khmer Rouge began to assume a greater role in Chinese foreign policy between November 1973 and April 1974. China was concerned with increased Soviet aid to the Vietnamese, and saw enhanced relations with Cambodia as a means to balance a Soviet-aligned Vietnam.110 Enhanced relations between China and Cambodia were realized in a May 1974 agreement, which provided the Khmer Rouge with free military equipment and supplies.111 In April 1975, Cambodia negotiated a Chinese military aid package of 13,300 tons of weapons.112 By mid-September, ‘China was prepared to extend to Cambodia a total of US$1 billion in interest-free economic and military aid, including an immediate $20 million gift’.113 This was reportedly ‘the biggest aid ever given to any one country by China’.114

China anointed the Sino-Khmer alliance on 28 September 1977.115 However, Chinese leaders still sought to exercise a ‘moderating influence’ on the Khmer Rouge, and to point the regime ‘in the direction of a more traditional realpolitik foreign policy’.116 According to a November 1978 US Interagency Intelligence Memorandum, China may have been ‘unhappy with some of the policies of the present Khmer regime’, but it still considered ‘an independent Kampuchea allied with Peking an essential buffer against the expansion of Vietnamese, and by extension Soviet, influence in the area’.117 China hoped ‘to thwart Vietnamese ambitions by providing strong support for Kampuchea’. In its bid to prevent Vietnamese regional expansion, China became ‘the principal source of military and economic aid to Kampuchea’.

With Chinese aid and firm domestic control, Pol Pot began to eliminate all Vietnamese influence in Cambodia from 1977. Cambodia openly declared a cessation in diplomatic relations with Vietnam on 31 December 1977.118 This was construed by the Vietnamese as ‘the (p.85) creation of a “bridgehead of aggression” on behalf of the Chinese’.119 The Vietnamese feared that Pol Pot was consolidating the Khmer Rouge position internationally, and gathering Southeast Asian and Western sympathizers.120 Seeking to put a halt to this process, the Vietnamese decided to remove Pol Pot as leader of the Kampuchean communist party. A US Intelligence Assessment reported that ‘Hanoi seems determined to bring a more malleable regime to power in Phnom Penh, while China shows no sign of willingness to soften its support of the current Cambodian leadership’.121

Vietnam’s invasion and its after effects

Following the Vietnam War, Vietnam’s domestic situation was in disarray. This was characterized by ‘acute food shortages, a steadily sagging economy, rampant official mismanagement, and cadre misbehaviour’.122 Unable to receive aid from countries such as the US and China, Vietnam was driven further into the arms of the Soviet Union. Vietnam joined the Comecon, a Moscow based economic arrangement, in August 1978. On 3 November 1978, it signed a treaty of Friendship and Cooperation with Moscow, which resulted in a massive shipment of Soviet military hardware to Vietnam.123 A closer relationship with the Soviet Union provided economic and military aid, as well as security assurances against an aggressive China. However, the increase in Soviet-Vietnamese relations led to a further decrease in Sino-Vietnamese relations.124 China viewed the treaty as a direct threat, believing it represented ‘another step in the Soviet effort to establish a collective security system in the region, ultimately directed against China’.125

China responded with a diplomatic effort to strengthen its regional relationships.126 The most important of these was enhanced relations with Thailand, which China believed could be used in a Vietnamese containment strategy.127 Two days after Vietnam signed the treaty of friendship with the Soviet Union, Deng travelled to Bangkok to seek more formal security cooperation.128 Deng assured the Thai Prime Minister, General Kriangsak Chamanan, that Beijing would end its support for the Communist Party of Thailand (CPT) and would punish Hanoi for its hegemonic behaviour.129 He also stated that China would help enhance Thai security against the Vietnamese threat. While Kriangsak did not immediately agree to a formal alliance, the meeting set the groundwork for future enhanced relations.

With Soviet economic and security assurances, Vietnam now felt in a position to take action against an increasingly aggressive Cambodia. A (p.86) hostile Cambodia posed a serious threat to Vietnamese security. Apart from Cambodia’s close physical proximity to Vietnam, Cambodia’s relationship with China allowed an external power a regional presence in Indochina. It was vital for Vietnam that Cambodia be prevented ‘from becoming springboards for attacks on its territory or havens for organizing insurgencies’.130 Vietnamese attempts to remove Pol Pot began during 1977, with a series of shallow military incursions that sought to trigger a military coup in Phnom Penh, or to spark a civil war.131 When these attempts failed, the Vietnamese attempted to create a liberation movement within Cambodia in mid-1978. While successful, the Vietnamese came to the decision that the strategy was too protracted. As such, in December 1978, the Vietnamese decided on a third strategy, ‘the highly visible big unit war’.132 The first phase of the assault commenced on 25 December 1978, when between 150,000 and 220,000 Vietnamese troops invaded neighbouring Cambodia.133 On 7 January 1979, Pol Pot was driven from Phnom Penh by Vietnamese troops, supported by some 20,000 dissident Cambodians.134 Elements of the Khmer Rouge survived, including approximately 20–40,000 troops, which withdrew to the jungle.135 On 8 January, a Vietnamese puppet government, titled the Kampuchean United Front for National Salvation (FUNSK), was installed, headed by Heng Samrin, a former Khmer Rouge defector who fled to Vietnam during the regime purges.

On 31 December 1978 and 3 January 1979, Deputy Prime Minister in charge of Foreign Affairs of Democratic Kampuchea, Ieng Sary, charged Vietnam ‘with intensifying acts of aggression against his country, including ground and air attacks, pillaging, burning and killing’.136 Sary requested an urgent meeting of the UN Security Council to condemn Vietnam’s attack.137 On 4 January, a Vietnamese representative transmitted two December FUNSK declarations to the UN, which charged that ‘the regime of Prime Minister Pol Pot and Foreign Minister Ieng Sary of Democratic Kampuchea had usurped power, transformed the revolutionary forces into mercenaries for the Chinese authorities, and threatened the Kampuchean people with extermination’.138 A Vietnamese representative transmitted further documents to the UN on 8 January concerning the liberation of Phnom Penh, stating that ‘any meeting of the Security Council to hear the representative of the Pol Pot regime would constitute intervention in the internal affairs of the Kampuchean people’.

The UN Security Council met from 11 to 15 January at the request of Democratic Kampuchea, and from 23 to 28 February at the request of Norway, Portugal, the United Kingdom and the US. At each (p.87) meeting, a draft resolution calling for cessation in hostilities and a demand for strict adherence to non-interference was rejected, owing to the negative vote of the USSR [Union of Soviet Socialist Republics]. The Soviet Union objected to these resolutions, as it considered FUNSK ‘to be the genuine and sole representative of the Kampuchean people, and that the situation in that country was an internal matter’.139 The Council extended an invitation to the delegation of Democratic Kampuchea, and a representative reiterated that ‘his country was the victim of large-scale aggression by Viet Nam (sic), supported by the USSR’. In a letter to the UN on 20 February 1979, Vietnam transmitted the text of a Treaty of Peace, Friendship and Cooperation between the Socialist Republic of Vietnam and the People’s Republic of Kampuchea, signed at Phnom Penh on 18 February by Heng Samrin and Pham Van Dong.140 This effectively consolidated Vietnam’s influence in Cambodia and hegemonic position in Indochina.

China’s plan to teach Vietnam a lesson

Vietnam’s invasion of Cambodia drew an immediate Chinese response. In a letter to the UN dated 7 January 1979, China charged that Vietnam ‘had invaded Democratic Kampuchea, was occupying a large part of the country and, with USSR support, intended to annex Kampuchea by force and set up an “IndoChinese Federation” under its control’.141 In a meeting between President Carter and Premier Deng on 29 January 1979, Deng argued that ‘the Vietnamese now are extremely arrogant. They now claim to be even the third most powerful military nation in the world, after the United States and the Soviet Union … we consider it necessary to put a restraint on the wild ambitions of the Vietnamese and to give them an appropriate limited lesson’.142 With regard to potential Soviet reprisals, Deng believed that the Soviet Union ‘did not have adequate forces to conduct any large military operations against China immediately’.143 He expressed the belief that ‘if our action in the South is quickly completed, they won’t have time to react … we need your [the US] moral support in the international field’.144

However, Carter was not quick to give this support. He informed Deng that ‘this is a serious issue. Not only do you face a military threat from the North, but also a change in international attitude … it could result in escalation of violence and a change in the world posture from being against Vietnam to partial support for Vietnam.’

(p.88) Carter followed this with an oral presentation to Deng on 30 January, confirming the US belief that a punitive strike against Vietnam ‘would be a serious mistake … the United States could not support such action, and I strongly urge you not to approve it’. Deng was unmoved by Carter’s presentation, insisting that China ‘are forced to make the decision to take necessary self-defense operations against Vietnam. This operation will be restricted and limited in scope … it may play a certain role to check the ambitions of Vietnam and will benefit peace and stability of this region’. Having informed the US of China’s intentions, Deng then set out to woo the ASEAN countries, embarking on a nine-day tour through Thailand, Malaysia and Singapore, with the task of assuring ‘these countries of China’s benevolent role as guardian of regional security and to enlist their support in the confrontation with Vietnam’.145

China’s military action against Vietnam came approximately two weeks after Deng’s visit to Washington. US Secretary of Defence, Harold Brown, believed this was ‘clearly Deng’s intent … to use security relations with us [the US] as a means of constraining the USSR’.146 On 10 February 1979, Vietnam transmitted an urgent message to the UN from its Deputy Prime Minister and Minister for Foreign Affairs, which ‘charged that China had recently intensified armed activities at the Vietnamese frontier in preparation for war’.147 On 17 February, the Chinese government issued a statement arguing that ‘because Vietnamese authorities had ignored China’s warnings and repeatedly encroached on Chinese territory and attacked Chinese frontier guards and inhabitants, China had been forced to counter-attack’.148 On 18 February, a representative from the Soviet Union charged ‘China with aggression against Viet Nam, blatantly flouting international law and exposing the essence of Peking’s hegemonic policy in Southeast Asia’.149

The Sino-Vietnamese border war was fought in three stages, beginning on 17 February, and ending with a complete withdrawal on 16 March.150 It involved 400,000 Chinese troops,151 and was the largest People’s Liberation Army (PLA) military operation undertaken since the Korean War.152 The attack caught Hanoi off-guard, forcing them to resist the Chinese advance whilst requesting immediate aid from Moscow. The Chinese claimed the war to be a victory, with more than a dozen border cities captured and 57,000 Vietnamese soldiers wounded or killed.153 The Vietnamese claimed they lost several cities, but only after killing and wounding 42,000 Chinese troops.154 However, the PLA were willing to absorb heavy losses, as long as the conflict achieved its strategic goals. The PLA believed (p.89) these goals had been achieved, and that the war had succeeded in ‘exposing Moscow’s inability or unwillingness to back Vietnam’.155 While the use of force against Vietnam had been condemned by the US, albeit ambiguously, and raised the suspicions of regional states such as Indonesia and Malaysia, ultimately there was very little backlash, regionally or internationally.

Emergence of the ASEAN vanguard state

ASEAN responded to Vietnam’s invasion of Cambodia with a diplomatic effort at the UN. On 9 January, Indonesia issued a statement from its Minister for Foreign Affairs, as Chairman of the ASEAN Standing Committee, expressing ‘grave concern’ over the escalation of the conflict between Cambodia and Vietnam.156 The convening of a UN Security Council meeting was requested to discuss the situation in Indochina. On 12 January, Indonesia issued a joint statement of a special meeting of the ASEAN Foreign Ministers held in Bangkok, in which the Ministers, ‘deplored the armed intervention in Kampuchea, affirmed the right of the Kampuchean people to determine their future by themselves; [and] called for the immediate withdrawal of foreign forces from Kampuchean territory’.157 An ASEAN Foreign Ministers joint statement was also released on 13 January in relation to Indochinese refugees displaced due to conflict in Cambodia. The ASEAN ministers ‘expressed their grave concern over the increasing influx of these persons into ASEAN countries … the influx is encountering severe economic, social, political and security problems particularly in the countries bearing the main brunt of the influx, such as Thailand and Malaysia’.158

ASEAN submitted two further letters to the UN in 1979. On 20 February, Indonesia issued a statement by the Chairman of ASEAN’s Standing Committee, ‘appealing for a cessation of hostilities and withdrawal of all foreign forces from all areas of conflict in Indo-China’.159 This statement became the basis for a draft UN resolution, sponsored by the five ASEAN countries, to be considered at a Security Council meeting on 16 March. By this text, the Council urgently called upon all parties to ‘cease all hostilities forthwith, withdraw their forces to their own countries and settle their disputes by peaceful means’. On 17 August 1979, the ASEAN states sent a letter to the UN, requesting inclusion of an item on ‘The situation in Kampuchea’ in the agenda of the General Assembly’s 34th (1979) session. The General Committee considered this request on 19 December, where Thailand (p.90) argued that ‘the armed conflict in Kampuchea was creating a refugee problem and thereby imposing immense strain on neighbouring countries’. China supported inclusion of the item, ‘charging Viet Nam with aggression against Democratic Kampuchea, which, it said, posed a serious threat to the security and stability of Southeast Asia’.

The General Committee decided, by 19 votes to 5, with one abstention, to recommend that the General Assembly include the item in its agenda. On 14 November, the General Assembly adopted resolution 34/22 by which it ‘called for the immediate withdrawal of foreign forces from Kampuchea’. The resolution was adopted by a vote of 91 to 21, with 29 abstentions. The ASEAN Ministers decided to explore the possibility of a settlement to the Cambodia conflict, by dispatching the Malaysian Foreign Minister, Tengku Ahmad Rithauddeen, to Hanoi as an ASEAN representative.160 Although the Vietnamese would not accept Rithauddeen as an ASEAN envoy, he did visit the Vietnamese capital as Foreign Minister of Malaysia from 9–11 January 1980. During this meeting, the Vietnamese ‘refused to discuss the presence of their forces in Kampuchea’.161

ASEAN’s internal debate

Despite the joint ASEAN statements released following Vietnam’s invasion of Cambodia, the conflict did not immediately create cohesion within ASEAN. There still remained disagreement over the major source of threat, and what should be done about it. There was, however, a general feeling that Vietnam’s attempt to placate the ASEAN states in 1978 had been a ‘duplicitous stratagem’, and a ‘manoeuvre to soften them as part of Vietnam’s preparations to invade Cambodia’.162 Moscow’s funding of the campaign also ‘hurt its image’163 in the region, with states of the opinion that Moscow ‘had attempted to gain illegitimate entry into the region’.164 The alliance between Moscow and Hanoi also badly damaged ASEAN confidence in Vietnamese claims to be a nonaligned nation.165 Despite this general feeling, certain ASEAN states continued to feel some sympathy for the Vietnamese. Indonesia and the Philippines indicated that they ‘did not consider that Vietnam posed any threat to ASEAN’.166 Indonesia remained particularly concerned about the regional role of China, with both Indonesia and Malaysia preferring to pursue a ZOPFAN in Southeast Asia, for fears that they were becoming trapped in a wider Sino-Soviet dispute. According to this view, enhanced Soviet regional influence might lead to a situation where ‘China was using ASEAN for (p.91) its own political objectives, and ASEAN was implementing Chinese policies’.167 These states were also concerned that taking a hard stance against Vietnam might bring about either ‘a debilitated Vietnam subject to China’s dominance or a debilitated Vietnam bound in a permanent client relationship to the Soviet Union which would in turn reinforce the Thai-Chinese relationship’.168

Even Thailand wished to maintain some façade of neutrality. The Thai Prime Minister, General Kriangsak Chamanan, stated his government’s formal position of neutrality in a visit to Moscow in 1979, hoping to gain assurances against an aggressive Vietnam, and to placate Moscow as to Thailand’s relationship with China.169 However, this was merely pretence to seek great power assurances. Both Thailand and Singapore viewed Chinese aid ‘as a bellwether for stability’.170 The lack of regional cohesion meant that Thailand felt dissatisfied with the level of support offered by the ASEAN states. Thailand showed this dissatisfaction through local news reports, stating ‘concern in the Foreign Ministry that other countries had not shown they were prepared to fully support Thailand in the event of an attack on it by Vietnam’.171 The Thai government wanted ‘its regional partners [to] stand up and be counted in a collective demonstration of ASEAN solidarity’.172

Two events can be credited with enhancing institutional cohesion in 1979 and early 1980. The first was the influx of refugees into Southeast Asia from Indochina. The problem of Cambodian refugees in Thailand was the topic of several communications to the UN Secretary General during June and August 1979.173 In a letter to the UN dated 23 October, Thailand stated that 100,000 Cambodians had entered Thailand as a result of fighting.174 Many in the ASEAN states believed that Vietnam was sending ‘out the “boat people” to destabilize the countries of the southeast where they land, and that this is done with Moscow’s encouragement’.175 The second event was a series of armed incursions by Vietnamese troops against camps in Thailand. Representatives of Thailand alleged violations of Thai territory during October and November 1979. Thailand claimed that on 14 and 21 October, 1 and 23 November and 27 December, mortar rounds fired from Cambodian territory had landed in Thai territory, and troop intrusions and shellings had killed and wounded Thai civilians, thus violating Thai neutrality.176 Vietnam responded with statements transmitted on 28 November and 21 December 1979, which ‘charged Thailand with colluding with the remnants of the Pol Pot-Ieng Sary regime and creating tension on the Thai-Kampuchean frontier by tolerating the use of Thai territory for supply centres and sanctuaries for combatants’.177

(p.92) The influx of refugees into Southeast Asia, coupled with Vietnamese incursions into Thailand, had the effect of ‘obliging wavering members of ASEAN to close ranks once more in support of the Association’s front-line state’.178 From that point, ‘ASEAN became more explicit in its challenge to Vietnam’, and the ‘political fortunes of ASEAN were made hostage to solidarity with Thailand’.179 By May 1979, the Malaysian Prime Minister had made a successful visit to China, indicating a shift away from Vietnam.180 Malaysia also cancelled aid and technological cooperation agreements with Vietnam, tripled the size of its air force and doubled the size of its army.181 The Philippines announced a $200 million increase in its military budget, and Indonesia ordered 60 army battalions to be brought to full strength.182 From 1979, ‘military planning in Indonesia, Malaysia, Thailand, and Singapore … shifted from internal, counter-insurgency warfare to preparation for conventional warfare’.183

The presence of the Soviet Pacific Fleet in the South China Sea and Indian Ocean encouraged Malaysia to agree to the basing of Australian P3-C reconnaissance aircraft.184 Singapore went so far as to propose military cooperation with external powers and to call upon ASEAN to aid Khmer Rouge guerrillas in their fight against the Vietnamese.185 As the front-line state, Thailand obtained $30 million credit for arms purchases and military aid from the US, with additions bringing the total aid package to $400 million.186 Thailand also increased the army by 20 battalions, a one-third increase.187 From 1979 onwards, the ASEAN states were forced to seek additional military assistance from the US. In 1982, Indonesia, Philippines and Singapore sent military delegations to Washington to discuss arms purchases. In 1984, the Thai air force group sought to purchase F-16 fighter-bombers.188 Reliance on external power security guarantees meant that ASEAN’s aspiration for a ZOPFAN in Southeast Asia had ‘given way to a more real-politik [underlining in text] security formulation’.189

ASEAN’s internal debate: a summary

Evidence suggests that by the end of 1979, Thailand had assumed the role of ASEAN vanguard state. ASEAN support was an important component in Thailand’s anti-Vietnam policy. Thailand made it clear to the ASEAN states that it expected total commitment in the face of Vietnamese aggression, in addition to enhanced regional relations with extra-regional powers. While this policy was unpopular with certain ASEAN states, the influx of refugees into Southeast Asia, (p.93) coupled with Vietnamese incursions into Thailand, had the effect of increasing solidarity for Thailand, as the front-line ASEAN state with the most compelling interests at stake in the conflict. Although these events did not erase lingering concerns regarding the role of external powers in the region, they did have the effect of creating a united ASEAN front, which was used to great diplomatic effect at the UN.

ASEAN vanguard state – external power interest convergence

On 13 January 1979, several senior staff members of the PLA flew to meet with Thai premier Kriangsak. The following day ‘was spent in long sessions discussing the modalities of Sino-Thai cooperation in the Cambodian war … it was at that secret meeting between Chinese and Thai military leaders that a foundation of de facto Sino-Thai alliance was laid’.190 China was in desperate need of Thai support, as noted in a US telegram from the Embassy in China, in which it stated that ‘Beijing’s strategy is heavily reliant on Thai cooperation … if the Vietnamese spill over into Thailand, the risk of a major PRC military strike against Vietnam will be commensurately greater’.191 As part of the Sino-Thai alliance, Kriangsak agreed to allow the Chinese use of Thai territory to support the Khmer guerrillas.192 This arrangement began as soon as cooperation between the two was formalized. With Thailand and the Khmer Rouge, China had created a united front against Hanoi expansionism.

China and the ASEAN states also encouraged a continued American regional presence. In a conversation between President Carter and Vice Premier Deng on 29 January 1979, Carter confirmed that the US is ‘encouraging the ASEAN countries to stand united against Vietnam, and we are increasing military aid to Thailand’.193 Deng agreed with this approach, stating that, ‘at least a majority of ASEAN countries assesses this [as] an extremely grave matter … ASEAN countries are now in the front line’. Throughout 1979, China continually stressed the importance of Thailand in the fight against the Vietnamese. In July 1979, National Security Council Staff members Nicholas Platt and Richard Holbrooke visited Beijing to meet Foreign Minister Huang Hua. On his return, Platt reported to US National Security Advisor Brzezinski that Hua ‘stressed the threat to Thailand, where seven Vietnamese divisions are poised on the border. If Thailand goes, “the rest of ASEAN will fall like dominoes”’.194

(p.94) In an August 1979 meeting between US Vice President Walter Mondale and Chinese Vice-Premier Deng, Mondale stated that ‘in Indochina, we share the same objectives: to create an independent Kampuchea that is not threatening to its neighbors, to prevent Laos from falling further under Vietnam and Soviet sway, to protect Thailand and other ASEAN states, and to show Vietnam that its increasing dependence upon Moscow will hurt badly over time and should be abandoned.’195 Mondale stated that the US ‘understand Thai and other ASEAN concern … the US stands ready to work closely with China and with ASEAN in making progress to this end’. Deng was adamant that the most important ‘conditions for a political settlement must be the genuine independence of Kampuchea and the withdrawal of Vietnamese troops from the country’. Deng insisted that ‘any political settlement that departs from these two preconditions is in fact aiding the Vietnamese and aiding the Russians’.

The Sino-Thai alliance did not mean that Bangkok and Beijing always shared the same view. Unlike China, ‘it was not ASEAN’s objective to humiliate Vietnam’.196 Vietnam was only perceived as a threat due to its invasion of Cambodia. Singapore stated its desire for ‘a strong, independent and prosperous Vietnam, rather than a Vietnam which was a satellite of China’.197 This difference in Sino-ASEAN viewpoints provided Thailand with an additional, diplomatic role, whereby Thailand could ‘serve as a link and facilitator between China and Southeast Asia’.198 In an October 1980 visit to Beijing, Thai Prime Minister Prem Tinsulanond secured Chinese ‘willingness to consider ASEAN’s proposal to create a coalition resistance government that would include non-communist forces as well as the Khmer Rouge’.199 Thailand also sought to alleviate tensions between the PRC and ASEAN at a UN international conference in July 1981. Thailand persuaded ASEAN countries to move closer to the Chinese position on the need for the Khmer Rouge, as well as patching up misunderstandings, and alleviating lingering concerns regarding China’s true intentions.200

ASEAN vanguard state resistance to sovereignty violation

In an August 1979 meeting between US Vice President Walter Mondale and Chinese Vice-Premier Deng, Mondale informed Deng that the US have ‘placed major emphasis on the closest consultation with ASEAN countries including improved security assistance to Thailand, more modern planes, more economic assistance and (p.95) military assistance’.201 Deng agreed with Mondale’s support for the ASEAN states, stating that ‘ASEAN countries particularly Thailand, Malaysia, and the Philippines have expressed their apprehension that the Vietnamese may attack them, and I told them in the event of an attack against the ASEAN countries, we will stand on their side. And I told them that we mean what we say’. Thailand was at the forefront of this support. In a meeting between President Carter and Premier Hua in July 1980, Carter informed Hua that the US ‘had expedited shipment by air to Thailand of some weapons they had ordered’.202 Hua stated that China was making ‘every effort to assist the Thais, including shipments of “natural resources”’. China was also ‘taking pressure off Thailand by tying down 29 SRV [Soviet Republic of Vietnam] infantry divisions along the Sino-Vietnamese border’. As an added element of security, Hua had informed ‘the Thais that the PRC would “side with them” if Vietnam made another large-scale attack into Thailand’.

Security cooperation was clearly in the interests of both Thailand and China following Vietnam’s invasion of Cambodia. The informal security alliance that developed between Thailand, ASEAN, China, the US and the ousted Khmer Rouge was a counter-encirclement strategy that sought to contain the Soviet and Vietnamese threat.203 Although China received permission from Thailand to aid the Khmer Rouge through Thai territory, Thailand received security guarantees that greatly enhanced its ability to resist Vietnamese aggression.204 Thailand was now in a position to ‘report Vietnamese shellings or attacks on the Thai border and expect that within six hours the Chinese troops on the Sino-Vietnamese border would repay the Vietnamese in kind’.205

While it is unclear whether Vietnam would have invaded Thailand, thus violating Thai sovereignty, there existed the belief, both regionally and among the external powers, that Thailand could be the next domino to fall. If this did occur, the rest of Southeast Asia was under increased threat. China, the US, Malaysia and Indonesia all promised to assist Thailand in case of a Vietnamese attack.206 While ASEAN could provide ‘collective political defence,’ it could not provide ‘countervailing power’.207 As such, Thai responses to the Vietnamese invasion of Cambodia ‘involved large power diplomacy’.208 As an ASEAN vanguard state, Thailand played the important and necessary function of actively seeking and supporting great power intervention in regional affairs, which was consistent with the interests of both Thailand and the external actor in question, China. By doing so, Thailand, as an ASEAN vanguard state, had an active and substantial role in resisting sovereignty violations from a Soviet-backed Vietnam.

(p.96) The regional environment 1980–1991

Without the capabilities to provide a military response to Vietnam’s invasion of Cambodia, ASEAN resorted to a diplomatic initiative at the UN. It was vital that ASEAN portray a united front, to prevent international recognition of the Heng Samrin puppet regime in Phnom Penh. This diplomatic initiative began in 1979, and continued for the duration of the conflict, with the ASEAN states also lobbying the UN repeatedly regarding refugee flows from Cambodia, and Vietnamese incursions into Thai territory. The credentials of the delegation of Democratic Kampuchea also became a topic for debate at the UN, which were examined by the Credentials Committee on 22 September 1980.209 Singapore took the position that ‘if Democratic Kampuchea were to lose its seat in the United Nations, it would be tantamount to saying that it is permissible for a powerful military state to invade its weaker neighbour, to overthrow its government and to impose a puppet regime on it’.210 China, Singapore and the US stated that ‘Democratic Kampuchea was a Member State of the United Nations and its Government was the sole legal representative of Kampuchea; therefore its credentials were in order’.211 However, ‘both Singapore and the United States indicated that they continued to deplore that Government’s human rights record’.212

This had been a point of contention among the US, China and the ASEAN states. Deng argued that ‘in deciding to form a united front we cannot exclude Pol Pot because Democratic Kampuchea is practically the only force of resistance now in Kampuchea’.213 However, the United States claimed that ‘if Pol Pot is the sole focal point of resistance to Heng Samrin, the situation is likely to get worse’.214 In July 1979, the US announced a policy of recognizing neither the Pol Pot nor the Heng Samrin governments.215 The Assembly voted to reject any amendment to the credentials of Democratic Kampuchea by a vote of 35 in favour to 74 against, with 32 abstentions.216 Democratic Kampuchea said that ‘rejection of the amendment had helped to prevent Viet Nam from legalizing its invasion of Kampuchea’.217 In October 1980, the General Assembly adopted resolution 35/6, by which it decided to convene in 1981 ‘an international conference on Kampuchea to seek a political settlement’.218

The International Conference on Kampuchea was held in New York on 13–17 July 1981, with a mandate to seek a comprehensive political settlement of the Cambodian problem.219 At the conference, 79 member states participated. A proposal by Singapore that ‘three political groups be invited to participate without vote was approved with respect to the (p.97) Khmer People’s National Liberation Front [KPNLF] and the National United Front for an Independent, Neutral, Peaceful and Co-operative Cambodia’. The Conference ‘referred to its Bureau the question of the participation of the People’s Revolutionary Party of Kampuchea’. The KPNLF was a political front formed by Son Sann, a former Prime Minister of Cambodia, who opposed the Heng Samrin regime. Prince Sihanouk formed the National United Front for an Independent Neutral Peaceful and Co-operative Cambodia with the encouragement of the ASEAN states, which hoped to provide a more credible alternative for Cambodia than that offered by the ousted Khmer Rouge.

The International Conference on Kampuchea adopted a Declaration setting out elements for negotiation and resolution of the conflict, which included ‘withdrawal of all foreign forces from Kampuchea; restoration and preservation of its independence, sovereignty and territorial integrity; and a commitment by all states to noninterference in its internal affairs’. The Declaration was approved on 21 October 1981 by the General Assembly, which adopted resolution 36/5 by a recorded vote of 100 to 25, with 19 abstentions. This resolution reiterated that ‘withdrawal of all foreign forces and the Kampuchean people’s right to determine their own destiny were principal components of any resolution of the problem’. The Assembly also noted a joint statement issued by Singapore on 4 September, in which ‘Prince Norodom Sihanouk, Son Sann and Khieu Samphan [a leading figure within the Khmer Rouge] expressed the desire to form a coalition Government of Democratic Kampuchea’.

Stalemate at the United Nations

In a communiqué on the Kampuchea situation issued on 18 June 1981, the ASEAN Foreign Ministers ‘proposed a political settlement including United Nations peacekeeping forces, foreign troop withdrawal and the disarming of all Khmer factions’.220 Following elections held by the Vietnamese regime in Cambodia, the Philippines Foreign Minister, as Chairman of the ASEAN Standing Committee, transmitted a statement on 25 March ‘by which the ASEAN members denounced the elections as an attempt by the Heng Samrin regime to legitimize itself’.221 Thailand also continued to make submissions to the UN Secretary General complaining of incursions from Cambodian territory by Vietnamese-Heng Samrin forces. This included over 80 separate violations between June 1980 and January 1981,222 something vigorously denied by Vietnam.

(p.98) On 22 June 1982, Prince Sihanouk, Khieu Samphan, and Son Sann signed the Declaration of the Formation of the Coalition Government of Democratic Kampuchea (CGDK) at Kuala Lumpur. Under the coalition, these became President, Vice President in charge of Foreign Affairs and Prime Minister, respectively.223 Vietnam responded to the Coalition Government by calling it a ‘farce that had been in production by China and the United States for over a year, and it regretted support of that farce by the Association of Southeast Asian Nations’.224 Despite the formation of the CGDK, ‘virtually all Chinese supplies were channelled only to the Khmer Rouge’.225 China blamed ‘the Sihanouk forces’ lack of organization and the KPNLF’s factionalism as explanations for China’s refusal of military assistance to them’.226

Having reached a stalemate, the Cambodian crisis remained unresolved for the majority of the 1980s. The General Assembly continued to call for a lasting solution to the conflict,227 and the ASEAN Foreign Ministers continued to release joint statements appealing to ‘efforts towards a just solution of the Kampuchea situation so as to restore Kampuchea’s status as an independent and sovereign state’.228 The ASEAN states also continued to call upon Vietnam to engage in talks with the Coalition Government of Democratic Kampuchea. In a joint statement issued 8 July 1985 by the ASEAN Foreign Ministers, it was reported that the ‘Coalition Government of Democratic Kampuchea had informed them that it was ready to enter into exploratory indirect or “proximity” talks with Viet Nam … to discuss the basic elements of a comprehensive, political settlement’.229 In a 9 October 1985 letter from the Chairman of the ASEAN Standing Committee, it was reported that ‘Viet Nam had not responded positively to ASEAN’s proposal’.230

Indonesia’s diplomatic initiatives: the Kuantan principle

Despite committing itself to providing a united ASEAN response to the invasion of Cambodia, Indonesia believed ‘that a compromize should be reached between ASEAN and Vietnam’, and this ‘was reflected in Indonesia’s unilateral diplomatic attempts to soften Vietnam’s position’.231 Within Jakarta, there existed some resentment regarding the ‘shift in the political centre of gravity of the Association from Jakarta to Bangkok … [which] had the effect of diminishing Indonesia’s assumed position of corporate leadership’.232 For Jakarta, Thailand’s Vietnam policy ‘and its implication for ASEAN … had been described as “the Thai tail that wags the ASEAN dog”’.233 Still (p.99) motivated by fear of China, Indonesia and Malaysia continued to seek a diplomatic settlement with Vietnam that deviated from China’s ‘bleed Vietnam white’ strategy.234 These attempts were articulated in March 1980 in the Kuantan principle, which was largely a reiteration of the 1971 ZOPFAN declaration.235 In an effort to reduce great power influence in the region, the principle proposed that ‘Vietnam would agree to cut its Soviet ties … if Thailand delinked from China and the Khmer Rouge’.236 The statement also ‘pointedly took cognizance of Vietnam’s security interests in Indochina’.237

In doing so, Indonesia and Malaysia confirmed that they were prepared to accept Vietnamese hegemony in Cambodia, in return for reduced tensions at the Thai-Cambodian border and a reduction in great power meddling in the region.238 Despite Indonesian and Malaysian efforts, the Kuantan principle was never implemented. This was largely due to a failure to gain either Chinese or Vietnamese endorsement for the proposal.239 The declaration also ‘proved to be totally unacceptable to Bangkok’.240 As the state most threatened by Vietnam, Thailand would ‘quietly sabotage any initiative that it perceived as against Thai interest’.241 During a tour of ASEAN capitals, General Prem Tinsulanond, ‘went out of his way in both Kuala Lumpur and Jakarta to indicate hostility to the Kuantan message’.242 ASEAN concessions were not acceptable to Thailand or Singapore, which ‘publicly stood by the earlier ASEAN resolution calling for a complete withdrawal of Vietnamese forces’.243 Ultimately, President Suharto ‘was not prepared to test the cohesion of the Association for the sake of a divisive joint formulation whose practical application was uncertain’.244

Jakarta Informal Meeting (JIM)

Despite the failure of the Kuantan principle, Indonesia maintained its efforts to engage with Vietnam diplomatically. Recognizing this, the ASEAN states designated Jakarta the role ‘official ASEAN interlocutor’ with Vietnam.245 Indonesia made two unpublicized trips to Hanoi in 1980 and 1982 to find a compromize to the Cambodian conflict. A third, official, trip came on 13–15 February 1984.246 From 25–28 July 1988, Indonesia invited representatives from the four Cambodian parties, Prince Sihanouk from the National United Front for an Independent Neutral Peaceful and Co-operative Cambodia, Son Sann from the KPNLF, Khieu Samphan from the Party of Democratic Kampuchea, and authorities in Phnom Penh, headed by Hun Sen – (p.100) as well as the Lao People’s Democratic Republic, Vietnam and six members of ASEAN to meet for discussions at a cocktail party in Jakarta, later titled the Jakarta Informal Meeting (JIM). One positive outcome from the JIM was that all parties to the Cambodian crisis met for the first time, ‘even though their respective positions remained incompatible’.247 For Indonesia, the process was ‘an opportunity to take a higher international profile’.248 However, this did not mean Suharto had deviated from ASEAN’s collective approach to the conflict. Suharto recognized that ‘the unity and solidarity of ASEAN is more important than the maintenance of good bilateral relations with Vietnam’.249 A second Jakarta Informal Meeting (JIM II) took place from 19–21 February 1989. Singapore noted ‘a more substantive convergence of interests amongst the three – Indonesia, Vietnam and the PRK – to work out a “regional solution” which could resist Sino-Soviet pressure’.250

Thailand, on the other hand, ‘adopted a generally low-key role at JIM II which they were not supportive of in the first place’.251 Singapore also noted that ‘the JIM process reflected the Indonesian assessment that Indonesia and Vietnam, as the two major powers in the region, should shape regional order and not let the external powers dominate’.252 However, the meeting revealed disagreements on certain aspects of the settlement of the Cambodia conflict, particularly ‘the establishment of a provisional quadripartite authority of national reconciliation under the leadership of Prince Sihanouk’.253 Despite failing to provide a diplomatic solution to the Cambodian problem, and despite continued difference among the ASEAN member states, Suharto continued to maintain public solidarity with ASEAN on the issue of Cambodia.254

The end of the Third Indochina War

On 5 April 1989, Vietnam announced the decision to withdraw all of its troops from Cambodia by the end of September.255 Vietnam announced that this had been completed between 21 to 26 September 1989.256 These steps towards conciliation coincided with a change in Soviet leadership. Mikhail Gorbachev became leader of the Soviet Union in March 1990. Faced with increased domestic and economic problems, Gorbachev realized that ‘ameliorating the Sino-Soviet conflict and disengaging China from the Western security system was a far more important objective than having good relations with Vietnam and significant influence in Indochina’.257 China placed conditions on (p.101) normalization of relations with the Soviet Union, one of which was that Moscow cease support of Vietnam in Cambodia.258

A subsequent reduction in Soviet economic and military aid left Vietnam effectively abandoned. Military aid to Vietnam was ‘almost exclusively’ Soviet.259 By the 1980s the Soviet Union was providing Vietnam with 97 percent of its military hardware. This was a marked increase from 1975, when the Soviet Union was only providing 75 percent.260 Vietnam was unable to support its wartime economic and military policy in Cambodia without Soviet aid. Faced with a change in the status quo, Vietnam had little option but to capitulate to China. Beijing offered ‘reduced border tension and lower defence costs in return for Vietnamese withdrawal from Cambodia’.261 As Vietnam began to withdraw all of its troops from Cambodia, China eased tensions along the Sino-Vietnamese border and began to improve diplomatic relations between the two. In August 1990, the four Cambodian parties accepted a framework for a comprehensive political settlement, drawn up by the five permanent members of the UN Security Council.262 The Cambodian parties agreed to form a Supreme National Council (SNC) that would represent Cambodia at the United Nations.263 With the basis for a Cambodian settlement arranged, and with an end to the Cold War in sight, the Third Indochina War came to an official end on 23 October 1991.

Theoretical assessment of the Third Indochina War (1978–1991)

After many years of seeking a diplomatic solution to the Cambodian conflict, the ASEAN states ultimately had little say in its conclusion. This was because the conflict was essentially a product of great power Cold War rivalry. However, ASEAN and its supporters maintain the view that the Association played a key role in preventing the Vietnamese regime in Cambodia from receiving international recognition. Undoubtedly, Thailand, and by extension ASEAN, played an important role in the conflict. They did so in order to secure Thailand’s own interests, which were to prevent sovereignty violations from a Soviet-backed Vietnam. Thailand therefore had an active and substantial role in resisting sovereignty violations from other external powers. But an equally important factor is the role played by China, and to a lesser extent, the US. Had it not been for the informal alliance that developed, it is highly likely that Thailand would have resigned itself to Vietnamese domination in Indochina. ASEAN alone did not (p.102) have the capabilities to reverse Vietnam’s Cambodia policy, or to stand against Vietnam if it had sought to expand into Thailand. This suggests that convergence of both ASEAN vanguard state and external actor interests are necessary to secure ASEAN vanguard state resistance to sovereignty violation.

The case of the Third Indochina War can be understood in terms of a realist theoretical logic. The Soviet Union and Vietnam posed a clear threat to the external powers and to the ASEAN states. They responded to this threat by engaging in external and internal balancing strategies, to secure the vital state interest of autonomy and security. This interest convergence between an ASEAN vanguard state and external actor caused ASEAN vanguard state resistance to sovereignty violation, from actors external to the region. Can ASEAN be conceptualized as a unitary actor when Thailand was the vanguard state? Based on the foregoing analysis, ASEAN can be conceptualized as an actor during those periods when ASEAN displayed a united front in support of vanguard state interests. Evidence of minor deviations from cohesion should not result in denial of group actor designation.264 Accordingly, those deviations from unitary action made by Indonesia and Malaysia during the Cambodian conflict do not result in denial of group actor status, because these deviations did not compromize the united front that ASEAN portrayed from late 1979 till the end of the conflict in 1991.

Analysis has shown that in the case of the Third Indochina War, behavioural cohesion was a response to the external threat posed by the Soviet Union and Vietnam. According to Stephen Walt, ‘external threats are the most frequent cause of international alliances’.265 Facing a threat, states seek to engage in balancing behaviour because ‘they place their survival at risk if they fail to curb a potential hegemon before it becomes too strong’.266 State interests are therefore premised on the basic point of seeking survival. This is consistent with the work of Crawford and Press, who define vital state interests as involving ‘self-preservation, political independence, and, by extension, defence of strategically vital areas’.267 As the evidence has shown, in its pursuit of survival, Thailand actively sought maximum great-power commitment to its security interests.268 In conjunction with the rest of ASEAN, Thailand was able to affect the regional distribution of power by adding to the resources of China and the US while constraining that of Vietnam and the Soviet Union.269 The case in question therefore meets vanguard state theory’s expectations.

(p.103) Contrasting theoretical arguments

The consensus among the constructivists studying ASEAN is that the organization’s governing norms emphasize dialogue, consensus-building and non-confrontation. What happens when the organization’s norms are challenged? Constructivist theorists interpret the Third Indochina War as a challenge to ASEAN norms, cohesion and unity.270 However, their accounts of this case are at times limited, suggesting a need to look for alternative explanations. Ba states, ‘Vietnam’s action clearly challenged the idea of a unified and resilient Southeast Asia’, while Thailand’s subsequent alliance relationship with China ‘represented a real test of the regional autonomy goals’.271 Ba concedes that ‘it would take some rhetorical contortions to make Thai actions consistent with what was agreed should be the ASEAN project of regional resilience’.272 However, she continues to maintain that their ability to work together ‘provided an important affirmation of their efforts and [italics in text] their solidarity as a group’.273

Despite challenges, Ba maintains that ‘shared ideas of region and the importance of regional unity might … have been the only [italics in text] significant thing that kept them [ASEAN] working together toward a common solution’.274 In this view, ideas about Southeast Asia’s ‘division and foreign intervention’ find expression in ‘ideas of resilience and “One Southeast Asia”’.275 Arguably, this overestimates the role of ideas in the historical record of this case study. Evidence presented here suggests that ASEAN cooperation was actually based on regional security concerns, rather than shared ideas of regional unity. Ba’s analysis of the conflict also underemphasizes the important role played by external powers. Ba acknowledges that Thai actions ‘legitimat[ed] China’s involvement in Southeast Asia’.276 However, she fails to examine the critical role China, and the US, played in the conflict’s resolution. This presents an account of the conflict that is at odds with this period of Southeast Asia’s history.

Other constructivists maintain that the Third Indochina War was a success for ASEAN, which emerged from the conflict strengthened in its mission and core norms. According to Acharya, ASEAN ‘presented the Vietnamese invasion as a gross violation of the principle of non-intervention in the internal affairs of states as well as the principle of non-use of force in interstate relations’.277 As events developed, the conflict gave ‘a more substantive meaning to ASEAN political and security cooperation’,278 while also having ‘positive effects for ASEAN’s pursuit of a regional identity’.279 In this view, the conflict ‘motivated ASEAN members to overcome conflicting security interests (p.104) and territorial disputes within the grouping, thereby moving it further on the path towards a security community’.280 The account presented here does not deny the record of ASEAN cooperation, but emphasizes that it has been misinterpreted. To be specific, the role of ASEAN has been elevated, while that of external powers has been systematically downplayed, with important theoretical consequences. Indeed, Jürgen Haacke, who has studied ASEAN’s diplomacy in the Third Indochina War, reaches a very different conclusion to Acharya, noting that ultimately, ‘all of ASEAN had to bow to the pressure of major powers and accept the political compromize [sic] that was presented as a fait accompli’.281

A second strand in the literature is represented by the realist perspective. Michael Leifer, David Martin Jones and Michael Smith contend that ASEAN’s preference for consensus and conflict avoidance has lent itself to extra-regional actors manipulating ASEAN norms to serve their own best interests.282 Leifer, Jones and Smith all view ASEAN’s role in the Cambodia conflict as subordinate to that of the external powers. According to Leifer, the role of China represented a ‘much more effective means by which to challenge Vietnam’s hegemonic position than the diplomatic support of ASEAN’.283 Because of this, the position ‘adopted by the Association favoured China’s interests, above all’.284 Jones and Smith also minimize ASEAN’s role in the resolution of the Third Indochina War, maintaining that the eventual settlement ‘represented an archetypal manifestation of great power politics’.285 According to this view, ‘ASEAN’s actual contribution to the Cambodian settlement reveals its role to be both ambiguous and ultimately limited’.286 The Association only appeared effective ‘because its actions coincided with superpower interests’, with ASEAN acting as ‘a convenient front for external actors and interests’.287 For Jones and Smith, the fact that China and the Soviet Union effectively resolved the conflict through bilateral diplomacy, illustrated ‘the region’s continuing dependence upon external actors and the illusory character of ASEAN’s attempt to erect a cordon sanitaire around Southeast Asia’.288

This perspective advanced by Leifer, Jones and Smith is difficult to reconcile with the facts. China and the US clearly saw ASEAN, and Thailand in particular, as a critical actor in opposing Vietnam. Any account of this case must therefore focus on the importance of Sino-Thai cooperation. While Leifer does give some consideration to the ‘differential impact on the actual security interests’ of the ASEAN member states, these are viewed as relatively ineffective.289 Thus, the alternative approaches to resolving the problem of Vietnam’s invasion (p.105) are interpreted as arising ‘from a natural divergence of strategic perspectives, which has been an important factor in denying the Association a conventional security role’.290 The critical point to note is that Leifer does not seek to develop a connection between external power and regional state interests. As such, ASEAN state interests remain hostage to those of China, and regional autonomy remains wholly reliant on external actors. For Jones and Smith, ASEAN only appeared effective because its actions coincided with the interests of China and the US. This approach takes an overly restrictive view of ASEAN autonomy and the role of ASEAN states. As this chapter has shown, Thailand also sought to secure its own interests as a response to the Vietnamese threat, and worked with ASEAN to prevent a Vietnamese fait accompli. Jones and Smith offer an accurate portrayal of the role of great powers in Indochina during the Cold War; they minimize the ASEAN role. As such, there remain limitations in their analysis.

For Lee Jones, ASEAN responded to Vietnam’s invasion of Cambodia ‘not to defend its non-interference principle, but rather to contain revolution in Indochina’.291 To this end, the ASEAN states ‘engaged in counter-intervention, fomenting civil war inside Cambodia to keep Vietnamese forces pinned down and unable to support revolutionary movements outside Indochina’.292 The Vietnamese threat is ‘not understood in conventional, military, balance-of-power terms’ but in terms of ‘the likely consequences of the invasion for the balance of forces within their own societies’.293 The differing ASEAN responses to the Vietnamese invasion are explained as ‘stemming from intra-elite splits and differences in domestic social conflicts’.294 Despite these differences, Jones maintains that ‘a shared determination to uphold capitalist social order in the region underpinned ASEAN’s basic cohesion’.295

Jones’ overwhelming focus on social conflict within individual ASEAN states leaves a number of important factors under-theorized. By focusing predominantly on the domestic politics of regional states, the role of external powers in the conflict has been minimized. Jones makes no mention of the role of the Soviet Union, despite the integral part Moscow had in the conflict. While Jones refers to China’s desire to counter ‘Soviet-initiatives’ in his narrative, his focus on the Sino-Thai relationship seems to consist largely of China’s reduced support for the CPT in Thailand, and the effect this had on Thailand’s social order.296 This focus on domestic factors underemphasizes the mutual security concerns of Thailand, China and the US, and deemphasizes legitimate and real fears of Vietnamese expansion on the (p.106) part of ASEAN states. Moreover, as evidence provided in this chapter has shown, ASEAN’s basic cohesion in the aftermath of the invasion was less to do with a determination to uphold capitalist social order, and more to do with concerns for regional security. These concerns were exacerbated after the influx of refugees into the region, and Vietnamese incursions into Thai territory. These important facets of the Third Indochina War case study are missing from Jones’ argument, suggesting the need for an additional approach.

As this chapter has instead attempted to show, a realist external actor-ASEAN interest convergence model is effective in explaining ASEAN’s resistance to sovereignty violation during the Third Indochina War. Interest convergence between Thailand and China regarding the Vietnamese threat meant that Thailand (and by extension ASEAN) was able to resist sovereignty violation from an expansionist Vietnam. Conversely, China was able to use Thailand, and by extension ASEAN, to support its Vietnam policy in Southeast Asia.


(1) Content from this chapter originally published in Journal of Asian Security and International Affairs, Vol. 2 No. 2. Copyright 2015 © SAGE Publications India Private Limited, New Delhi. All rights reserved. Reproduced with the permission of the copyright holders and the publishers, SAGE Publications India Pvt. Ltd, New Delhi.

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