Conflict	Cambodia-Vietnamese War
Partof	Third Indochina War, Indochina Wars, Cold War
Caption	Vietnamese-led forces entering Phnom Penh in 1979.
Date	May 1975 – September 1989 Large scale fighting lasted between 25 December, 1978 and 7 January, 1979(invasion of Democratic Kampuchea by Vietnamese forces until the fall of Phnom Penh).
Place	Cambodia, southern Vietnam, eastern Thailand
Result	Vietnamese military victory.
Combatant1	Vietnam People's Republic of KampucheaSupported by: Soviet Union
Combatant2	Democratic KampucheaSupported by: China
Commander1	Le Duc Anh
Commander2	Pol Pot Khieu Samphan Son Sann Norodom Sihanouk
Strength1	150,000-200,000 Vietnamese soldiers
Strength2	1979: 73,000 1989: 30,000
Casualties1	1979–1989:15,000 killed30,000 wounded
Casualties2	1979: 15,000 killed ~40,000 captured
Campaignbox

The Cambodian–Vietnamese War was an armed conflict fought within the geopolitical context of the Cold War involving the Socialist Republic of Vietnam and Democratic Kampuchea. The war began with limited objective campaigns along the land and maritime boundaries of Vietnam and Kampuchea between 1975 and 1977, occasionally involving division-sized military formations. On 25 December 1978, Vietnam launched a full-scale invasion of Kampuchea and subsequently occupied the country after the Khmer Rouge was removed from power.

During the Second Indochina War, the Vietnamese and the Khmer Rouge communists had formed an alliance to fight U.S.-backed regimes in their respective countries. Despite their open display of cooperation with the Vietnamese, the Khmer Rouge leadership feared that the Vietnamese communists were scheming to form an Indochinese federation with themselves as the dominant force in the region. In order to preempt an attempt by the Vietnamese to dominate them, the Khmer Rouge leadership began purging Vietnamese-trained personnel within their own ranks as the Lon Nol regime capitulated in 1975. Then, in May 1975, the newly-formed Democratic Kampuchea, dominated by the Khmer Rouge, began waging a war against Vietnam, which was marked by an attack on the Vietnamese island of Phu Quoc. In spite of the fighting which had occurred between the two countries, the leaders of reunified Vietnam and Kampuchea made several public diplomatic exchanges throughout 1976 to highlight the supposedly strong relations between them. Behind the scenes, however, Kampuchean leaders continued to fear what they perceived as Vietnamese expansionism. As such, on 30 April 1977, they launched another major military attack on Vietnam. Shocked by the Kampuchean assault, Vietnam launched a retaliatory strike at the end of 1977 in an attempt to force the Kampuchean Government to negotiate. In January 1978, the Vietnamese military withdrew because their political objectives had not been achieved.

Small-scale fighting continued between the two countries throughout 1978, as China tried to mediate peace talks between the two sides. However, neither country could reach an acceptable compromise at the negotiation table. By the end of 1978, Vietnamese leaders decided to remove the Khmer Rouge-dominated regime of Democratic Kampuchea, perceiving it as being pro-Chinese and too hostile towards Vietnam. On 25 December 1978, 150,000 Vietnamese troops invaded Democratic Kampuchea and overran the Kampuchean Revolutionary Army in just two weeks. On 8 January 1979, a pro-Vietnamese People's Republic of Kampuchea (PRK) was established in Phnom Penh, marking the beginning of a ten-year Vietnamese occupation. During that period, the Khmer Rouge's Democratic Kampuchea continued to be recognised by the United Nations as the legitimate government of Kampuchea, as several armed resistance groups were formed to fight the Vietnamese occupation. Behind the scenes, Prime Minister Hun Sen of the PRK regime approached factions of the Coalition Government of Democratic Kampuchea (CGDK) to began peace talks. Under heavy diplomatic and economic pressure from the international community, the Vietnamese Government implemented a series of economic and foreign policy reforms, which led to their withdrawal from Kampuchea in September 1989.

At the Third Jakarta Informal Meeting in 1990, under the Australian-sponsored Cambodian Peace Plan, representatives of the CGDK and the PRK agreed to a power-sharing arrangement by forming a unity government known as the Supreme National Council (SNC). The SNC's role was to represent Cambodian sovereignty on the international stage, while the United Nations Transitional Authority in Cambodia (UNTAC) was tasked with supervising the country's domestic policies until a Cambodian government was elected by the people through a peaceful, democratic process. Cambodia's pathway to peace proved to be difficult, as Khmer Rouge leaders decided not to participate in the general elections, but instead, they chose to disrupt the electoral process by launching military attacks on UN peacekeepers and killing ethnic Vietnamese migrants. In May 1993, Sihanouk's FUNCINPEC movement defeated the Cambodian People's Party (CPP), formerly the Kampuchean People's Revolutionary Party (KPRP), to win the general elections. However, the CPP leadership refused to accept defeat and they announced the eastern provinces of Cambodia, where most of the CPP's votes were drawn from, would secede from Cambodia. To avoid such an outcome, Norodom Ranariddh, the leader of FUNCINPEC agreed to form a coalition government with the CPP. Shortly afterwards, the constitutional monarchy was restored and the Khmer Rouge was outlawed by the newly-formed Cambodian Government.

Background

Cambodian-Vietnamese history

Vietnam began exercising its influence over Cambodia as early as the Angkor civilization in the thirteenth century. Its influence spread gradually and indirectly, and it was not until the early nineteenth century that Vietnam exercised direct control. In 1813, Nak Ong Chan gained the Cambodian throne with the help of Vietnam, and under his rule Cambodia became a protectorate (Ibid). Following his death in 1834, Vietnam colonised Cambodia; it was governed under a Vietnamese administration and termed a Vietnamese ‘province’. Throughout the 1830s, Vietnam attempted to erase the Khmer culture, which had derived the basis of its society, dress and religion from India rather than China. The trend of Vietnamese dominance continued during French colonisation, under which Cambodia was forced to cede much of its southern cone (what would be Saigon, the Mekong delta and Tay Ninh) to the Vietnamese. Attempts to regain this territory later became the justification for border incursions committed by the Khmer Rouge regime prior to the Vietnamese invasion.

Rise of communism

The communist movement in Cambodia and Vietnam began before World War II with the founding of the Indochinese Communist Party (ICP), almost exclusively dominated by the Vietnamese, originally meant to fight French colonial rule in Indochina. In 1941, Nguyen Ai Quoc (commonly known by his alias Ho Chi Minh) founded the Viet Nam Doc Lap Dong Minh Hoi, or the Viet Minh. When the Japanese were defeated at the end of World War II, he initiated the first Indochinese war of independence against the French. During this time, Vietnamese forces greatly used Cambodian territory to transport weapons, supplies, and troops. This relationship lasted throughout the Vietnam War, when Vietnamese communists used Cambodia as a transport route and staging area for attacks on South Vietnam. In 1951, Vietnam guided the establishment of a separate Cambodian communist party, the Kampuchean People's Revolutionary Party (KPRP), which allied with a nationalist separatist Cambodian movement, the Khmer Serei (Free Khmers), in order to pursue independence. In accordance with the 1954 Geneva Accords negotiating the end of the French domination, newly created communist North Vietnam pulled all of its Viet Minh soldiers and cadres out of Cambodia; however, since the KPRP was staffed primarily by ethnic Vietnamese or Cambodians under its tutelage, approximately 5,000 Communist cadres went with them.

The leftist vacuum Vietnam left in its wake in Cambodia was soon filled by the return of a young group of revolutionaries, many of whom received their communist education in France. In 1960, the KPRP changed its name to the Kampuchean Communist Party (KCP), which was later adopted by the majority coalition that formed around Saloth Sar (Pol Pot), Ieng Sary and Khieu Samphan as the ‘true’ date memorialising the KCP. This clique became the genesis of the Khmer Rouge, and it embodied the communist branch most influenced by Maoist doctrine.

Democratic Kampuchea and the Khmer Rouge

The Khmer Rouge government adopted the mysterious term Angkar, or "the organisation", and until 1977 the identities of its leaders remained confidential. The official head of state was Khieu Samphan, but the two men in control of the Party were Pol Pot and Ieng Sary. The ultimate objective of the Khmer Rouge was to erase the structure of the Cambodian state, which they viewed as feudal, capitalist, and oriented around the agendas of both the landholding elite and imperialists. In its place, they hoped to create a classless society based entirely on worker-peasants. The radical ideologies and goals of the Khmer Rouge were alien concepts to the masses. In fact, the socialist revolution held very little popular appeal, which led Pol Pot and his cadres to use ultra-nationalist sentiment, repressive and murderous rule, and propaganda aimed at demonising the Vietnamese to maintain their tenuous control.

During the five years of the Khmer Rouge rebellion from 1970–1975, the support of North Vietnam, in conjunction with China, was essential to its eventual triumph. However, even before the Vietnam War ended, the relationship between the Khmer Rouge—which was in the process of seizing power from a US-backed regime headed by Lon Nol—and Vietnam was strained. Clashes between Vietnamese communists and Khmer Rouge forces began as early as 1974, and the following year Pol Pot signed a treaty codifying the ‘friendship’ between the Khmer Rouge and China.

Diplomacy and military action

1975-76, from fighting to building friendly relations

The conclusion of the Indochina conflict in April 1975 immediately brought a new conflict between Vietnam and Kampuchea. Although both the North Vietnamese and the Khmer Rouge had previously fought side by side, the leaders of the newly created Democratic Kampuchea continued to view North Vietnam with great suspicion, because they believed the Vietnamese Communist had never given up their dream of creating an Indochinese federation with Vietnam as the leader. For that reason, the Kampuchean Government decided to remove all North Vietnamese military forces from Kampuchean territory shortly after their capture of Phnom Penh in 1975. In the first major clash between the two former allies, the Kampuchean Revolutionary Army invaded the Vietnamese island of Phu Quoc on 1 May 1975, which they claimed was part of Kampuchea’s sovereignty. In response, in June 1976, the Kampuchean leadership sent a message to the Provisional Revolutionary Government of the Republic of South Vietnam, which had governed South Vietnam since the fall of the U.S.-backed regime, congratulating them on the seventh anniversary of their establishment.

In July 1976, following the establishment of the Socialist Republic of Vietnam as a reunified country, Phnom Penh Radio broadcast a commentary which proclaimed the “Militant Solidarity and Friendship between Peoples of Democratic Kampuchea and the Socialist Republic of Vietnam Grow Constantly Greener and Sturdier”. Nonetheless, on 21 September 1976, the first air service connecting Hanoi and Ho Chi Minh City with Phnom Penh was established. Then in December 1976, the Kampuchean Revolutionary Organisation sent greetings to the Vietnamese Communist Party on the occasion of its Fourth Congress. Indeed, that was the reason North Vietnam supported the Khmer Rouge during their fight against the Lon Nol regime, in the hope that the Kampuchean communists would adopt a pro-Vietnamese line upon their victory in the same way the Pathet Lao had done. However, their hopes were dashed as early as 1973, because North Vietnamese military formations operating in Khmer Rouge-occupied territories were subjected to armed attacks by their own allies. The Vietnamese position inside Kampuchea was further weakened after the end of the war, as there were no pro-Vietnamese elements left within the Kampuchean Communist Party.

Thus, when the pro-Chinese Pol Pot and his brother-in-law Ieng Sary resigned from their respective positions as Premier and Foreign Minister in September 1976, Vietnamese Prime Minister Pham Van Dong and General Secretary of the Communist Party Le Duan were optimistic that Vietnam could exercise greater influence on the Kampucheans. In a private meeting with the Soviet ambassador to Vietnam on 16 November 1976, Le Duan dismissed both Ieng Sary and Pol Pot as "bad people" for their pro-Chinese policies.

As the Kampuchean Revolutionary Army made preparations for its war against Vietnam, state-controlled media in Vietnam sent congratulatory messages to the Government of the Democratic Kampuchea on the second anniversary of its establishment, on 17 April 1977. On 30 April 1977, the second anniversary of the fall of Saigon, the Kampuchean reply came in the form of a military attack against the Vietnamese provinces of An Giang and Chau Doc, killing hundreds of Vietnamese civilians.

Both sides ignored each other’s proposals, and the Kampuchean Revolutionary Army continued sending soldiers across the border to attack Vietnamese towns and villages. In September 1977, Kampuchean artillery struck several Vietnamese villages along the border, and six villages in Dong Thap Province were overrun by Kampuchean infantry. Shortly afterwards, six divisions of the Kampuchea Revolutionary Army advanced about into Tay Ninh Province, where they killed more than 1,000 Vietnamese civilians. Angered by the scale of Kampuchean assaults, the Vietnam People’s Army assembled eight divisions, estimated at around 60,000 soldiers, to launch a retaliatory strike against Kampuchea. On 16 December 1977, Vietnamese divisions, with support from elements of the Vietnam People's Air Force, crossed the border along several axes with the objective of forcing the Kampuchean Government to negotiate. On 6 January 1978, Vietnamese divisions were only from Phnom Penh, but the Vietnamese Government decided to withdraw its forces from Kampuchea because they had failed to achieve Vietnam’s political objective. During the withdrawal, the Vietnamese military also evacuated thousands of prisoners and civilian refugees, including future leader Hun Sen. In reality, Kampuchean leaders simply ignored the condition of the population in their own country and Vietnam; the Vietnamese, though poor, were in good physical condition, while Kampuchea’s population was physically and mentally exhausted from years of hard labour, starvation and disease. On 27 January 1978, Vietnam started calling on the Kampuchean military along the border regions to overthrow the Khmer Rouge regime. Meanwhile, Vietnamese government officials began conducting secret meetings with So Phim, the Khmer Rouge leader in Kampuchea’s Eastern Military Zone, to plan a military uprising backed by Vietnam. During that same period, military setbacks experienced by the Kampuchean Revolutionary Army in the Eastern Military Zone prompted Pol Pot to label the region as a "nest of traitors".

In order to purge the Eastern Military Zone of those he perceived to have been contaminated by the Vietnamese, Pol Pot ordered military units from the Southwest Zone to move into eastern Kampuchea and eliminate the "hidden traitors". Unable to withstand an attack from the Kampuchea Government, So Phim committed suicide while his deputy Heng Samrin defected to Vietnam. Meanwhile, the Vietnamese Communist Party Politburo was meeting in Hanoi to discuss its strategy for Kampuchea. It concluded that the Khmer Rouge regime was a proxy of China, which had been trying to fill the power vacuum following the withdrawal of the United States. As such, China was identified as Vietnam’s main enemy, and its client regime in Phnom Penh had to be removed by conventional military force, because the Vietnamese adaptation of the Maoist ‘people’s war’ had not been a success against the Khmer Rouge’s security apparatus.

During the second half of 1978, Vietnamese leaders devoted much of their energy towards the military campaign against the Khmer Rouge regime, by seeking political support from the Soviet Union. In a briefing with Vietnamese Foreign Ministry officials on 25 July 1978, the Soviet charge d'affaires in Hanoi was told that the Kampuchean Government had deployed 14 of its 17 regular army divisions and 16 local regiments along the border with Vietnam. Then, in early September 1978, Le Duan informed the Soviet ambassador that Vietnam aimed to “solve fully this question of Kampuchea by the beginning of 1979”. While Vietnam was laying the political foundation for the military campaign against Kampuchea, Soviet ships were reported to be unloading military hardware and ammunition in Cam Ranh Bay.In October 1978, Vietnamese radio broadcast what they claimed were accounts of uprisings against the Khmer Rouge regime, urging members of the Kampuchean military either to overthrow the ‘Pol Pot-Ieng Sary clique’ or defect to Vietnam.

In a major turning point in the triangle of Soviet-Vietnamese and Sino-Vietnamese diplomatic relations, and ultimately the Vietnamese invasion of Kampuchea, on 3 November 1978 a Treaty of Friendship and Cooperation was signed between Vietnam and the Soviet Union, guaranteeing the former of vital Soviet military aid in the scenario that China intervened. Later, in November 1978, a command and control headquarters was established for the planned invasion of Kampuchea, with Senior General Le Duc Anh taking full control of Vietnamese military units along the border areas. To replace earlier losses and augment its units along the border, the Vietnamese Government drafted 350,000 men into the military. While the new recruits were completing training, ten divisions were deployed to the border regions of Long An, Dong Thap and Tay Ninh Provinces. Vietnam also shifted three divisions based in Laos south towards the Laos-Kampuchea border.

Nonetheless, the final piece of the Vietnamese strategy emerged when Vietnam announced the formation of the ‘Kampuchean United Front for National Salvation’ (KUFNS) in the ‘liberation zones’ of Kampuchea. Hanoi claimed that KUFNS was an independent Kampuchean communist movement, with members drawn from all walks of life. Heng Samrin, formerly a member of the Khmer Rouge and commander of the Kampuchean 4th Division, was the chairman of the KUFNS Central Committee. Previously, the KUFNS was known as the Provisional Revolutionary Government of Kampuchea (PRGK), which consisted of 300 former Khmer Rouge cadres who defected to Vietnam. The PRGK regularly sent representatives abroad in search of support, before Vietnam abandoned the ‘people’s war’ concept in favour of a conventional military campaign, similar to the Soviet invasion of Czechoslovakia in 1968.

Not to be outdone by the Vietnamese military build-up, the Government of Democratic Kampuchea was busy strengthening its armed forces with Chinese support. In previous years, China had only provided the Kampuchean Revolutionary Army with a limited amount of arms and ammunition, but as relations with Vietnam worsened in 1978, Beijing established additional supply routes through Kampuchea and increased the volume of military hardware which travelled down each route. Despite enjoying generous support from China, the Kampuchean military could not withstand the Vietnamese offensive and suffered heavy casualties.Finally, on 25 December 1978, Vietnam launched a full-scale invasion using 13 divisions, estimated at 150,000 soldiers well-supported by heavy artillery and air power. Initially, Kampuchea directly challenged Vietnam’s military might through conventional fighting methods, but this tactic resulted in the loss of half of the Kampuchean Revolutionary Army within two weeks. Heavy defeats on the battlefield prompted much of the Kampuchean leadership to evacuate towards the western region of the country. On 7 January 1979, the Vietnamese Army entered Phnom Penh along with members of the KUFNS. On the following day, a pro-Vietnamese Kampuchean state, known as the People's Republic of Kampuchea (PRK), was established, with Heng Samrin as the Chief of State and Pen Sovan as Secretary-General of the Kampuchean People's Revolutionary Party.

The Khmer Rouge leadership, with much of its political and military structures shattered by the Vietnamese invasion, was forced to take refuge in Thailand, where it was warmly welcomed by the Thai Government. Despite the overwhelming economic challenges brought by the Khmer Rouge and the accompanying refugees, the Thai Government sheltered and protected the Khmer Rouge at Khao Larn camp in Trat Province. Meanwhile, in Phnom Penh, the new Kampuchean regime tried to rebuild the country’s economic and social life, which was largely destroyed by decades of political upheavals and constant warfare. However, the new Kampuchean Government’s effort to rebuild the country was severely hampered by the lack of educated and qualified personnel, as most educated people had either fled the country or were murdered by the Khmer Rouge regime during the previous four years. By the end of the year, the new regime’s attempts at nation-building were further challenged by several anti-Vietnamese resistance groups operating along the western regions of the country.

Response from the international community

Shortly after the fall of Phnom Penh to Vietnamese forces and their Kampuchean allies in January 1979, representatives of Democratic Kampuchea called for an emergency meeting of the United Nations Security Council, so Prince Norodom Sihanouk could present the deposed regime's case. Despite strong objections from the Soviet Union and Czechoslovakia, the UN Security Council gave Sihanouk this chance. Although Sihanouk distanced himself from the human rights abuses of the Khmer Rouge, he accused Vietnam of using aggression to violate Kampuchea’s sovereignty. As such, he demanded all UN countries to suspend aid to Vietnam and not recognise the Vietnamese-installed regime.

Between 16-19 February 1979 Vietnam and the new Kampuchean regime held a summit meeting which concluded with the two countries signing the Treaty of Peace, Friendship and Cooperation. Article 2 of the treaty stated that the security of Vietnam and Kampuchea were interrelated; thus they would help defend each other “against schemes and acts of sabotage by the imperialist and international reactionary forces”, thereby legitimising the presence of Vietnamese troops on Kampuchean soil. In response, the UN Credential’s Committee decided to recognise Democratic Kampuchea by a vote of six to three, despite the Khmer Rouge’s blood-stained record while in power. Accordingly, representatives of Democratic Kampuchea were allowed to be seated in the General Assembly, with strong support from China. By January 1980, 29 countries had established diplomatic relations with the People Republic of Kampuchea, yet nearly 80 countries still recognised the legitimacy of the deposed Democratic Kampuchea. At the same time, the Western powers and the member countries of the Association of South East Asian Nations (ASEAN) also voiced strong condemnation of Vietnam’s use of force to remove the Khmer Rouge regime. That view was shared by China, which went as far as accusing Vietnam of forcing Kampuchea into an Indochinese federation to serve as an outpost of Soviet global hegemony. The United States, which never maintained any form of diplomatic ties with the Khmer Rouge’s Democratic Kampuchea, showed strong support for the membership of their former enemy in the UN General Assembly, and echoed ASEAN’s call for an immediate withdrawal of Vietnamese military forces from Kampuchea. Fighting bogged down due to the maze of tunnels the Chinese encountered; nevertheless, the Chinese army captured Cao Bang on 2 March and Lang Son on 4 March, reportedly advancing towards Hanoi at a high speed, though not on good terms with its supply lines. The following day, however, the Beijing regime announced that it would not move deeper into Vietnam, apparently after meeting fierce and unexpectedly harsh resistance by the well trained and experienced Vietnamese forces, supplied with American technology left behind from the Vietnam War. Confident that the threat of invasion had been a success, the Chinese retreated, leaving a path of destruction spanning in their wake.With Chinese support lost after Vietnamese recapitulation, Kampuchea was left to fend for itself. Although Chinese total losses were estimated higher than those of the Vietnamese (12–50,000 compared to the Vietnamese death toll of approximately 10,000), the diversion of troops from Kampuchea facilitated a strong resurgence in Khmer Rouge insurgent operations, making it unavoidable for the young PRK regime in Kampuchea to implement conscription and require Vietnam to station a large portion of its army along the Sino-Vietnamese border.

Internal resistance to the new regime

When the Khmer Rouge regime was removed from power in January 1979, the Kampuchean people believed that peace and liberty would return to their country. Their beliefs were reinforced by the Constitution of the People’s Republic of Kampuchean, proclaimed in 1981, which specifically stated that Kampuchea is an independent, peaceful state where power belongs to the people. However, there was a deep contrast between what was written within the Kampuchean constitution and reality, because the Kampuchean people began to despair at what they viewed as the Vietnamese occupation of their country, rather than a liberation that had freed them from the brutality of Democratic Kampuchea. That perception was reinforced by the presence of Vietnamese advisers who worked at every level of Heng Samrin’s Kampuchean Government. In 1986, for example, there was one Vietnamese adviser for every Kampuchean cabinet minister and one adviser for each one of their three deputy ministers. Furthermore, it was reported that final decisions made by a Kampuchean minister had to receive final approval from the Vietnamese adviser, who usually dictated policies.

; 1979-1984. KPNLF camps shown in black.]] To resist the Vietnamese occupation of Kampuchea and the regime which they installed, the Khmer Rouge called on the Kampuchean people to unite and fight the Vietnamese. However, due to the brutality which they had experienced under the deposed regime, many Kampucheans believed that any political movement aimed at restoring national freedom must oppose both the Khmer Rouge and the Vietnamese. In response to such preconditions, two non-communist movements were formed to fight the Vietnamese occupation. The first group, a right-wing and pro-Western organisation, was formed in October 1979 by former Prime Minister Son Sann and was called the Khmer People’s National Liberation Front (KPNLF). The KPNLF operated from several refugee camps on the Thai-Cambodian border, where it controlled thousands of civilians. At its peak, the armed branch of the KPNLF were estimated to have between 12,000 and 15,000 fighters, but a third of that number were lost through fighting and desertions during the Vietnamese dry season offensive of 1984-85. Nonetheless, the KPNLF continued to operate in small groups, harassing the Vietnamese and their Kampuchean allies using guerrilla tactics.

The other non-communist organisation was the National United Front for an Independent, Peaceful, Neutral, and Cooperative Cambodia, formed by Sihanouk and known by its French acronym FUNCINPEC. The organisation was formed after Sihanouk had severed ties with the Khmer Rouge following his representation on its behalf at the UN Security Council. As the leader of FUNCINPEC, Sihanouk called on the UN General Assembly to expel Khmer Rouge representatives for their crimes while in power and to keep Kampuchea’s seat at the UN vacant on the basis that neither the Khmer Rouge nor the Vietnamese-installed PRK had the mandate to represent the Kampuchean people. He also criticised ASEAN for its continued recognition of the Khmer Rouge, and specifically Thailand for enabling Chinese arms shipments to travel through its territory to supply the notorious communist group. Despite the strength, effectiveness and popularity of the KPNLF and the FUNCINPEC, both resistance groups were plagued by internal divisions caused by the lack of unity, leadership struggles, corruption and alleged abuses of human rights.

In the early days of the Vietnamese occupation, the Kampuchean resistance groups had limited contact with each other due to their differences. Even though the Khmer Rouge enjoyed widespread international support, by 1980 the organisation was under pressure to reform itself from the international community. ASEAN, which had backed the Khmer Rouge throughout their diplomatic confrontations with the PRK regime at the UN General Assembly in 1979, urged the Khmer Rouge leadership to put its blood-stained image behind it in order to join forces with other non-communist movements. However, the idea of forming an alliance with the Khmer Rouge initially caused a certain degree of uneasiness within the leadership circles of the FUNCINPEC and the KPNLF, because both groups were weary about joining with a communist organisation well-known for its brutality. Nonetheless, early in 1981 Sihanouk and Son Sann began engaging in talks with Khieu Samphan, President of the deposed Democratic Kampuchea, to discuss the prospect of forming an alliance. On 22 November 1982 Singapore, with the backing of ASEAN, proposed that three organisations form a coalition government with equal decision-making powers within the alliance. Singapore’s proposal was welcomed by Sihanouk, who believed it was a fair deal for the non-communist movements. In May 1982, with the urging of Sihanouk, Son Sann decided to form a coalition government with the Khmer Rouge. By 1987, Democratic Kampuchea still held its membership at the UN General Assembly, even though it lacked four criterion of statehood which included people, territory, government and supreme authority within the borders of a country. Thus, more than just a military problem, Kampuchea quickly evolved into an economic and diplomatic problem for Vietnam on the international arena. Throughout the decade in which Vietnam occupied neighbouring Kampuchea, the Vietnamese Government and the PRK regime which it installed were placed on the periphery of the international community.

The international community’s political stance towards Kampuchea had a severe impact on the Vietnamese economy, already wrecked by decades of continuous conflicts. The United States, which already had sanctions in place against Vietnam, convinced other countries of the United Nations to deprive Vietnam and the People’s Republic of Kampuchea of much-needed funds by denying them membership to major international organisations such as the World Bank, the Asian Development Bank and the International Monetary Fund. In 1979 Japan stepped up the pressure by suspending all economic aid to Vietnam, and warned Vietnamese leaders that economic aid will only resume when Vietnam amends its policies towards Kampuchea, the Sino-Soviet rivalry and the problem of the boat people. Sweden, which was considered the staunchest supporter of Vietnam in the West, also considered reducing its commitments to the communist country as virtually every other country cancelled its aid. Furthermore, attempts to nationalise the economy of southern Vietnam after reunification only resulted in chaos, as economic output were driven down by dislocation of the general population. In addition to those failed economic policies, Vietnam maintained the fifth largest armed forces in the world, with 1.26 million regular soldiers under arms. Consequently, the Vietnamese Government had to spend one-third of its budget on the military and the campaign in Kampuchea, despite receiving $1.2 billion in military aid annually from the Soviet Union, thus further hampering Vietnam’s economic rebuilding efforts. In order to disengage from Kampuchea, Vietnam unveiled a five-phase strategy known as the K5 Plan in 1984, which was authored by General Le Duc Anh, who led the Vietnamese campaign in Kampuchea. The first phase required the Vietnamese military to capture the bases of armed groups in western Kampuchea and along the border with Thailand. The next phases included sealing off the border with Thailand, destroying local resistance groups, providing security for the population, and building-up the Kampuchean People’s Revolutionary Armed Force. Then, to help Vietnam implement its third Five Year Plan (1981-1985), the Soviet Union provided a sum of $5.4 billion to the Vietnamese Government for its expenditures, and economic aid ultimately reached $1.8 billion annually. The Soviet Union also provided 90 percent of Vietnam’s demand for raw materials and 70 percent of its grain imports.

, the capital of Kampuchea.]] To reengage with the international community, and to deal with the economic challenges brought by the changes in the Soviet Union and Eastern Europe, Vietnamese leaders decided to embark on a series of reforms. At the 6th National Party Congress in December 1986, newly-appointed General Secretary of the VCP Nguyen Van Linh introduced a major reform known as Doi Moi, the Vietnamese term for ‘renovation’, in order to fix Vietnam’s economic problems. However, Vietnamese leaders concluded that Vietnam’s dire economic situation came as a result of the international isolation which followed its invasion of Kampuchea in 1978, and that for Doi Moi to be successful it needed radical changes in defence and foreign policy. Subsequently, in June 1987, the Vietnamese Politburo adopted a new defence strategy in Resolution No. 2, calling for the complete withdrawal of Vietnamese soldiers from international duties, a reduction in the size of the army through a discharge of 600,000 soldiers and the establishment of a set ratio for military expenditures.

Then, on 13 May 1988, the Vietnamese Politburo adopted Resolution No.13 on foreign policy, which aimed to achieve diversification and multilateralisation of Vietnam’s foreign relations. Its main objectives were to end the embargoes imposed by UN members, integrate Vietnam with the regional and international community and ultimately attract foreign investment and development aid. As part of this change, Vietnam ceased to regard the United States as a long-term foe and China as an imminent and dangerous enemy. In addition, official Vietnamese propaganda stopped labelling ASEAN as a ‘NATO-type’ organisation. To implement the new reforms, Vietnam, with support from the Soviet Union, started transferring several years' worth of military equipment to the Kampuchean People's Revolutionary Armed Forces (KPRAF), which numbered more than 70,000 soldiers. The Vietnamese Ministry of Defense’s International Relations Department then advised its Kampuchean counterparts to only use the available equipment to maintain their current level of operations, and not to engage in major operations which could exhaust those supplies.

In 1988 Vietnam was estimated to have about 100,000 troops in Kampuchea, but, sensing that a diplomatic settlement was within reach, the Vietnamese Government began withdrawing forces in earnest. Between April and July 1989, 24,000 Vietnamese soldiers returned home. Then, between 21 and 26 September 1989, after 15,000 soldiers were killed and another 30,000 wounded during the 10-year occupation, Then, in March 1991, Vietnamese units were reported to have re-entered Kampot Province to defeat a Khmer Rouge offensive. However, Sihanouk did not accept the offer, even as preparations were made in Phnom Penh to receive him. Despite that failure, Hun Sen’s Kampuchean Government was able to persuade Cheng Heng and In Tam, both ministers in Lon Nol’s regime, to return to Kampuchea.

was constructed to commemorate the ousting of the Khmer Rouge regime on 7 January 1979, by Vietnamese and KUFNS forces.]] Vietnamese Foreign Minister Nguyen Co Thach urged all parties involved to separate Kampuchean problems into internal and external aspects. Therefore, to begin the process of restoring peace, the Vietnamese delegation proposed a two-stage plan that begins with internal discussions among the Kampuchean factions, followed by a roundtable discussion with all involved countries. The Vietnamese proposal won out at the meeting, but no agreements were reached. Furthermore, Buddhism was re-established as the state religion, and citizens were guaranteed the right hold private property.

On 23 October 1991, the Cambodian factions of the Supreme National Council, along with Vietnam and 15 member nations of the International Peace Conference on Cambodia, signed the Paris Peace Agreement. For the Cambodian people, two decades of continuous warfare and 13 years of civil war seemed to be over, although an atmosphere of uneasiness amongst the leaders of the Cambodian factions remained. In order to include the Khmer Rouge in the agreement, the major powers agreed to avoid using the word ‘genocide’ to describe the actions of the Government of Democratic Kampuchea in the period between 1975 and 1979. As a result, Hun Sen criticised the Paris Agreement as being far from perfect, as it failed to remind the Cambodian people of the atrocities committed by the Khmer Rouge regime., and gave UNTAC a broad mandate to supervise main policies and administration works until a Cambodian government was democratically elected.

On 14 November 1991, Sihanouk returned to Cambodia to participate in the elections, followed by Son Senn, a Khmer Rouge official, who arrived a few days later to set up the organisation’s electoral campaign office in Phnom Penh. As soon as he arrived at his office, Khieu Samphan entered and immediately telephoned the Chinese Government to save him. Shortly afterwards, an angry mob forced its way into the building, chased Khieu Samphan up the second floor and tried to hang him from a ceiling fan. Eventually, Khieu Samphan was able to escape from the building on a ladder with his face bloodied, and was immediately taken to Pochentong Airport, where he flew out of Cambodia. Thus, with the departure of Khieu Samphan, the Khmer Rouge’s participation in the election seemed doubtful.

In March 1992, the commencement of the UNTAC mission in Cambodia was marked by the arrival of 22,000 UN peacekeepers, which included troops from 22 countries, 6,000 officials, 3,500 police and 1,700 civilian employees and electoral volunteers. The mission was led by Yasushi Akashi. In June 1992, the Khmer Rouge formally established the National Union Party of Kampuchea, and announced that it would not register to participate in the upcoming elections. Furthermore, the Khmer Rouge also refused to disarm its forces in accordance with the Paris agreement. Then, to prevent ethnic Vietnamese from taking part in the elections, the Khmer Rouge started massacring Vietnamese civilian communities, causing hundreds of thousands of Vietnamese to flee Cambodia. Towards the end of 1992, Khmer Rouge forces advanced into Kompong Thom in order to gain a strategic foothold, before UN peacekeeping forces were fully deployed there. In the months leading up to the elections, several UN military patrols were attacked as they entered Khmer Rouge-held territory.

Despite ongoing threats from the Khmer Rouge during the elections, on 28 May 1993, FUNCINPEC won 45.47 percent of the vote, against 38.23 percent for the Cambodian People’s Party. Though clearly defeated, Hun Sen refused to accept the results of the election, so his Defense Minister, Sin Song, announced the secession of the eastern provinces of Cambodia, which had supported the Cambodian People’s Party. Prince Norodom Ranariddh, leader of FUNCINPEC and son of Sihanouk, agreed to form a coalition government with the Cambodian People’s Party so the country would not break up. On 21 September 1992, the Cambodian Constituent Assembly approved a new Constitution and Ranariddh became First Prime Minister, and he appointed Hun Sen as the Second Prime Minister. On 23 September 1991, the constitutional monarchy was restored with Norodom Sihanouk as the head of state.In July 1994, the Cambodian Government outlawed the Khmer Rouge for its continuous violations of the Paris Agreement. Most significantly, the Cambodian Government also specifically recognised the genocide and atrocities which occurred under Democratic Kampuchea. By 1998, the Khmer Rouge was completely dissolved.

Vietnam rejoins the world

The military occupation of Kampuchea had profound consequences for Vietnamese foreign policy. Since gaining independence in 1954, the Vietnamese communist perspective on foreign policy had been dominated by the need to maintain a world order of two camps, communist and non-communist. Indeed, the treaty of friendship that Vietnam signed with the Soviet Union, Laos and the People’s Republic of Kampuchea was consistent with that view. However, the ideological motivations of the Vietnamese communist leadership was proven to be limited and heavily flawed, as demonstrated by the 1979 condemnation of Vietnam after the collapse of the Khmer Rouge regime. In the years that followed, the Vietnamese Government was left isolated from the world and its efforts to rebuild the country were handicapped due to the lack of aid from the capitalist Western nations. Furthermore, the presence of Vietnamese military forces in Cambodia became an obstacle which prevented the normalisation of diplomatic ties with China, the United States and the member nations of ASEAN. To reduce the state of hostility along the border region, and ultimately normalise relations with China, the Vietnamese Government dropped all hostile references to China at the 6th National Party Congress in December 1986, and also adopted the Doi Moi policy. In August 1990, as the Cambodian Peace Plan, authored by Australian Foreign Minister Gareth Evans, was being endorsed by the UN Security Council, both China and Vietnam moved towards accommodation.

Early in September 1990, Vietnamese Prime Minister Do Muoi, General Secretary Nguyen Van Linh and former Prime Minister Pham Van Dong travelled to Chengdu, China, where they held a secret meeting with Chinese Prime Minister Li Peng and General Secretary of the Chinese Communist Party Jiang Zemin. On 17 September 1990, General Vo Nguyen Giap also made a trip to China and thanked the Chinese Government for its past assistance.

The end of the Cambodian conflict also brought an end the ASEAN-imposed trade and aid embargo which had been in place since 1979. In January 1990, Thai Prime Minister Chatichai Choonhavan publicly voiced his support for Vietnam, and the rest of Indochina, to gain admission into ASEAN. In the period between late 1991 and early 1992, Vietnam restored relations with several member nations of ASEAN. As a result, between 1991 and 1994, investments from ASEAN countries made up 15 percent of direct foreign investment in Vietnam. Aside from the obvious economic benefits, ASEAN also provided a peaceful environment that guaranteed Vietnam’s national security against foreign threats in the post-Cold War era, when Soviet aid was no longer available. Thus, on 28 July 1995, Vietnam officially became the seventh member of ASEAN, after leading ASEAN officials invited Vietnam to join at the ASEAN Ministerial Meeting in Bangkok in 1994. Then, in August 1995, the U.S. Liaison Office in Hanoi was upgraded to Embassy status, after U.S. President Bill Clinton announced a formal normalisation of diplomatic relations with Vietnam on 11 July 1995, thereby ending Vietnam’s isolation from the world.

See also

Ba Chuc Massacre

Khmer Krom

Nong Chan Refugee Camp

Nong Samet Refugee Camp

Sino-Vietnamese War

Vietnamese border raids in Thailand

Notes

;Footnotes

;Citations

References

External links

The Khmer Rouge National Army: Order of Battle, January 1976

The Fall of the Khmer Rouge

From Sideshow To Genocide: The Khmer Rouge Years

1979: Vietnam forces Khmer Rouge retreat

Meanwhile: When the Khmer Rouge came to kill in Vietnam

Second Life, Second Death: The Khmer Rouge After 1978

Journal of Southeast Asian Studies, 2001;32(02):195–210">Slocomb M. "The K5 Gamble: National Defence and Nation Building under the People's Republic of Kampuchea." Journal of Southeast Asian Studies, 2001;32(02):195–210

Category:Cold War conflicts Category:Democratic Kampuchea Category:People's Republic of Kampuchea Category:History of Cambodia Category:Indochina Wars Category:Khmer Rouge Category:Sino-Vietnamese War Category:Wars involving Cambodia Category:Wars involving Vietnam Category:Vietnam War Category:1978 in Cambodia Category:1978 in Vietnam Category:1979 in Cambodia Category:1979 in Vietnam Category:20th century in Cambodia Category:20th century in Vietnam Category:Cambodia–Vietnam relations

cs:Vietnamská invaze do Kambodže es:Guerra Camboya-Vietnam fr:Guerre Cambodge-Viêt Nam id:Perang Kamboja-Vietnam it:Guerra cambogiana-vietnamita hu:Kambodzsai–vietnami háború no:Den kambodsjansk-vietnamesiske krig pt:Guerra cambojana-vietnamita ru:Кампучийско-вьетнамский конфликт fi:Kambodžan–Vietnamin sota sv:Kambodjansk-vietnamesiska kriget vi:Chiến dịch phản công biên giới Tây-Nam Việt Nam zh:柬越戰爭