Was Cambodia really an ally to the United States?


Cambodia and the United States have undergone decades of the relations. Historically, while the United States was fighting its war to prevent its allies from falling into the communist’s hand, it tends to seek allies to join hands fighting alongside the wars. Thus, like the wars in Germany, China, and the Korean Peninsular, the United States often seeks support from its allies. Likewise, to avoid Indochina from falling into the hands of the communists, the United States was supporting France, the former colonial power in the region, to fight against North Vietnam from taking over South Vietnam. Along the process, neighboring countries like Thailand chose to become allies to the United States and supported the great power in fighting against the communist. On the one hand, Cambodia, a small country in the region, chose to embrace neutrality and avoid being an ally to both the capitalist and the communist. Due to Cambodia’s geopolitical and strategic importance, the United States decided to woo the small state to supporting its quest in fighting against the North Vietnamese. However, the persistence to become a neutral country had led the United States to become suspicious of Cambodia’s position. Thus, such position has led to confusion of whether Cambodia was in any point during the war period, an ally to the United States. To some scholars, during the 1970s, the new government which gained power from overthrowing the Prince through a coup, was somehow an ally to the United States. Scholars like Lawrence R. Sullivan, Chileng Pa, Carol A. Mortlan, Elizabeth Becker, Ira Hunt Augustus as well as the late King Norodom Sihanouk considered Lon Nol government to be America’s ally. As written by a Cambodian scholar, on his article published on 5 June 2014, Leng considered Lon Nol to be an ally to the Americans during Nixon administration. This paper will look into the relations between Cambodia and the United States in four different administrations namely Eisenhower administration, John F. Kennedy administration, Johnson’s and Nixon’s to explore if Cambodia really became an ally to the United States at any point of time while the United States was fighting the war in Indochina to prevent the fall of South Vietnam into the communists. In addition, the paper will also explore the changes in Cambodia’s position in the United State’s politics in Indochina.

Sihanouk and Eisenhower

First and foremost, Eisenhower’s administration is the start of when the United States was trying to establish relations with Cambodia. As mentioned by Clymer, the relations between the United States and Cambodia started when Dulles was making a visit to Phnom Penh to present the formula to the Sihanouk and the other officials. At this stage, Cambodia’s politics is more like a one-man show as the decisions within the bureaucracy and the foreign relations were mostly made and conducted by the Prince, Norodom Sihanouk. Though Cambodia started to accept America’s aid by signing the military Defence Agreement and an American Military Assistance Advisory Group, we can see that Cambodia were yet willing to accept the proposal by the United States as Sihanouk and his officials were afraid that the presence of the American in Cambodia would affect Cambodia’s own sovereignty as well as the independent foreign policy of the country. At this very stage, we could witness that the Prince was trying to establish the relations with the United States by going against those who opposed the American aid. From the very start of the relations between the two countries, the United States’ administration started to question and debated among themselves whether they should have given aid to Cambodia when the administration was being pressed to give aid to its reliable allies. In this regards, the United States was being bothered by the fact that Cambodia was a neutral country. Thus, as being aforementioned, the fact that the United States was being pressed within its own administration to provide aid to its reliable allies might have somehow raised the doubt whether Cambodia was qualified to be trusted comparing to America’s very own reliable allies such as Thailand and the Philippines. Furthermore, the United States was also irritated by Sihanouk’s friendliness toward China and Russia. The United States also became dissatisfied with the Prince and his country due to the fact that he had rejected the protection of SEATO. For this reason, the Americans came into conclusion that Sihanouk was not only non pro-American, but almost promoting pro-communist policies. As the American was not sure of the Prince’s position, they had then come up with an idea of replacing the Prince with the other suitable candidate who would best serve America’s interest. Those who supported the idea of removing the Prince were Mike Mansfield, McClintock, and Frank Valeo. Even if the Prince tried to keep his balance while dealing with both the United States and his communist counterparts, the trust between the two countries could easily be fragile as Sihanouk was informed in 1959 that there was a plot against him while the U.S’s allies, Vietnam and Thailand were supporting the plot. In this regard, the involvement of both the U.S’s allies had led the Prince to become suspicious that the United States was supporting the plot with its allies. The fact that the United States refused to solve problems that Cambodia was having with the Thai and the Vietnamese governments had further affected the relationships between Cambodia and the U.S. Henceforth, it can be implied that Cambodia was not as important as America’s allies.

Sihanouk and Kennedy

Unlike Eisenhower’s administration, the relations between John F. Kennedy’s administration and Cambodia were in a better position. America’s effort to clear the accusation from the South Vietnamese government that Viet Cong’s bases were found in Cambodia’s border impressed the Prince. Unlike Eisenhower who seemed to treat Sihanouk in a hard way, Kennedy used a softer approach. The fact that Kennedy was inviting the Prince to the United States had given Sihanouk a sense that he was taken seriously by Kennedy. Thus, at this point, we can see that the troubled relations between the United States and Cambodia, was about to be resolved. Moreover, the United States continued to provide more aid to Cambodia. In contrast, the increasing pace of hostilities in Vietnam in 1962 had made the relationship between Cambodia and the United States more complicated. Though the United States was supporting Cambodia for its effort to improve security in the border areas, Kennedy’s administration was unwilling to support the Prince’s desire to neutralize Vietnam. While Eisenhower’s administration was not willing to solve the problems between Cambodia and its allies, Thailand and Vietnam, Kennedy’s administration did the opposite. Dean Acheson represented Cambodia in the case of Preah Vihear Temple conflict, which led to Cambodia’s victory over Thailand. After the court’s decision, the administration smartly took the mediating role to avoid the clash between Cambodia and Thailand. Nevertheless, though Sihanouk disliked Diem, Sihanouk felt insecure toward the way that the Americans took Diem out from the political theatre. He believed that the United States would try to use the same approach towards him as they did to Diem. Moreover, Sihanouk also believed that overthrowing Diem put an end to the possibility of neutralizing Vietnam. In this case, though the relations between Cambodia and the United States seemed to improve during Kennedy’s administration, trust was still an issue between the two governments. Furthermore, the relations between the two countries started to get worse when the accusation that the United States was supporting Khmer Serei was actually true.

Sihanouk and Johnson

Though Kennedy tried to renew the fragile relationships with Cambodia, Johnson’s administration marked another hindrance for the two countries to strengthen their relationships. The attack on March 19 in one of the Cambodian villages, which led to the death of seventeen villagers, marked a complication to the relationship. As mentioned by Clymer, even if the incident was deliberated or not, it reflected the unimportance of Cambodia to Johnson administration. The issue got even worse when seventy-seven villagers were killed from the drop of yellow powder on Ratanakiri Province. The drop was said to have been done by the South Vietnamese planes. Thus, the incidence led the Prince to demand the Americans to accept the responsibility for the deaths of the villagers. Similar incidences had also taken place which led Cambodia to retaliate by shooting down American transport plane. Reflecting from the two administrations and their relations with Cambodia, Thailand, and Vietnam, we can see that Washington might have been feared that backing Cambodia on the problems that Cambodia was having with Thailand and Vietnam would risk alienating the two valuable and more predictable allies.

Since United States and Cambodia ended their relationship, Australia accepted the responsibility in representing the United States in Cambodia. Though the start of the relations went well, the United States began accusing Cambodia of allowing a large presence of Viet Cong armies across the Cambodian border. Even if the investigation from Stanley Karnow could not really find any evidence to support the allegation, the United States was still suspicious of the relations between Sihanouk and the communist. Furthermore, the American account had found that Sihanouk actually benefitted from Beijing and Hanoi by allowing military equipment to be shipped through Sihanouk Ville. Though President Johnson pressured the Thais and the Vietnamese to treat Cambodia better, the border clashes had further complicated the relationship between the United States and Cambodia. By 1967, Sihanouk still remained very critical toward the United States as he publicly claimed that the Americans were to be blamed for attracting the communists into the region even if there was not any communist presence in the region before. On the other hand, though Sihanouk publicly criticized the United States, the insurgence in Battambang Province made Sihanouk dislike the Vietnamese communists. 1967 was the period that the relationship between the United States and Cambodia became warmer again. For instance, the improved relationship can be witnessed by the visit of Jacqueline Kennedy to Phnom Penh. The visit was warmly welcomed and responded by Sihanouk. However, the warm relationship between the two countries did not last long. While Bowles was talking with Sihanouk regarding the respect of Cambodia’s sovereignty, neutrality, and territorial integrity, a few other border incursions took place. Yet, the Prince seemed to ignore the incidence as he also wanted to improve the relations with the Americans. Sihanouk’s effort to release the arrested vessel crews without getting anything in return could also be seen as the concession that Sihanouk was making in order to restore the relations with the Americans.

Sihanouk and Nixon

Though the relationships between Cambodia and Johnson was getting warmer at the end of Johnson administration, the United States and Cambodia had yet to consider one another as an ally. At the beginning of his leadership, Nixon tried to continue what Johnson had left for him in the administration. However, as mentioned by Clymer, America’s aim to restore the relationship with Cambodia was only for the sake of using Cambodia to gain advantages over its enemies in South Vietnam as the communist was using Cambodia’s territory as a transit point for supply. For this reason, how the United States was trying to take advantage from Cambodia had obviously revealed that the United States did not really treat Cambodia as an ally. As named by William Shawcross, Cambodia was just a “sideshow”. In addition, the fact that the United States considered Cambodia to be just a sideshow can be seen through the secret bombing which was planned by Nixon and Kissinger. Therefore, as noted by Clymer, the United States’ effort to improve relationships with Cambodia in Nixon’s administration was only incidental. Unlike Kennedy and Johnson, Nixon took a harsher decision in bombing the neutral country which his predecessor was trying to establish relations with. Though Sihanouk had claimed that he would turn a blind eye to the bombing if the Americans bombed the unpopulated area in order to force the Viet Cong out of his country, he made it clear that he would not tolerate if the bombing affected the villagers living in the area. As claimed by Nixon and Kissinger, the bombing took place on the unpopulated area of Cambodia. Yet, it was found that the areas that got bombed were not unpopulated though they were not heavily settled. As mentioned by Ben Kiernan, the bombing led to large population movements. In six months from February to August 1973, the accumulation of 257,00 tons of bomb fell on all populated areas in the countryside of Cambodia. Prior to the bombing, the administration was also informed by the Joint Chiefs in 1969 that many of the sanctuary areas were settled by Cambodian villagers. In addition, Nixon’s administration was committed to the bombing as the Robert Seamans said that it was President Nixon who wanted to send more B-52s on Cambodia.

While Nixon administration was seen to be trying to establish relations with the Cambodian government, once the Prince was ousted during his trip abroad, the Americans turned their back, and switched their support to the newly formed government of Lon Nol. Arguably, the coup was claimed to been supported by the Americans as it had been found that the CIA was getting involved in the coup. Instead of condemning the new government, the Americans recognized Lon Nol government by militarily and technically supporting Lon Nol in fighting against the communists. In 1970, the American began supplying weapons to Lon Nol government as well as dragging the Khmer Krom volunteers to support the Lon Nol government in fighting against the communists. Moreover, the United States was also trying to get the other countries to assist Lon Nol. In doing so, the Americans were able to get Australia and Indonesia to support Lon Nol government through aid and military training. In his 43rd message to the Khmer Nation on July 16, 1973 while he was in exile, the Prince condemned Lon Nol regime and Richard Nixon whom he referred to as Lon Nol’s boss for their deceitful and false propaganda in order to make the world believe that they were trying to put an end to the war. In addition, the exiled Prince also made a call for the Americans to stop providing aid to the Lon Nol regime and to withdraw immediately from the Cambodian territory.

While the United States was putting a hard effort in fighting the communist to avoid its allies from falling into the communist dominoes, its effort and its policies had become counter-productive to Cambodia. The use of defoliant in 1964 over Cambodia, had badly affected the rubber plantation which was a vital economic source to the kingdom. By 1969, one-third of the rubber plantation in Cambodia was being destroyed by the defoliant. The war led to an increase in the black market for rice as illegal sales of rice were found along the border to support the increasing number of the insurgents. Consequently, the black market affected the country’s revenue generation as the government could only sell one-third of the amount of rice that it had sold in the earlier years. The lack of rice led the government to force the rural famers to sell their rice to the government in the price below the market price. As a consequence, such act from the government angered the rural populations, which provided the opportunity to the rise of the Khmer Rouge. While the bombing was meant to destroy the Viet Cong’s base and to force the Viet Cong out of the country, the bombing had conversely forced the communist forces from both Vietnam and Laos to move further into Cambodia.

Analysis and Characterization of the Type of Relations Between Cambodia and the United States

To be able to observe whether the relations between Cambodia and the United States can be classified into an alliance, we shall look at how alliance is defined. As provided by Kraus and Singer, the alliance is based on written and formal agreement, treaty or convention among states pledging to coordinate their behaviour and policies in the contingency of military conflict. In addition, such agreement to be alliance is mostly voluntary. In their paper on minor powers, alliances, and armed conflict, they clearly differentiated alliance, alignment, and coalition. Unlike an alliance whose specific goal is to guarantee security and signatory’s integrity on the basis of collective military defence, an alignment covers any general commitment to cooperation and collaboration. Despite being defined specifically, the objectives of alignment are broad and vague. Thus, its objectives may involve different aspects including military, economic, political, and cultural issues. On the other hand, coalition aims to establish commitment to coordinate states’ behaviour and policies so that they can pursue specific goals. Unlike alliance, coalition might focus on a single military or non-military issue.

Reflecting from the interactions and the ways in which the two countries were engaging, we can see that the conflicting interests between the two countries are the reasons behind the troubled relationship between them. From one American administration to another, the way in which the Americans tried to approach Cambodia changed respectively. Though Eisenhower administration provided aid to Cambodia, they were not ready to consider Cambodia as an ally. In this regard, the administration was unclear whether providing aid to Cambodia was a good option while its two allies were in need of more aid. Thus, we can see that the United States did not put Cambodia in the same position as Thailand and South Vietnam though Cambodia was strategically and politically important to them. On the one hand, Kennedy administration used a softer approach in dealing with Cambodia. Though both the administration were not really keen on Cambodia’s neutrality, Kennedy administration was the one which made Sihanouk feel that he was taken Seriously by the Americans. The relationship between Johnson administration and Cambodia was disturbed by the border incursions by the South Vietnamese troops into Cambodia. However, the insurgence from the communist within the country had made Sihanouk more inclined to the United States. In contrast, Nixon administration is the period when the relationship between Cambodia and the United State became eroded. The hard approach that Nixon had taken to deal with Cambodia destroyed the relations that the former administrations were trying to build. With its effort to support the Lon Nol government and engaged Cambodia into the war, Nixon administration ended up having another helpless government to protect from the communist.

In the case of Lon Nol and the Americans, though the Americans supported Lon Nol administration both militarily and financially, the relation between Lon Nol government and the United States was also full of uncertainties. For this reason, as mentioned by Clymer, Lon Nol was trying to approach the Indonesians and the Soviet embassy officials to serve as the intermediaries between his government and the North Vietnamese counterpart. As further provided by Clymer, the United States did not have any treaty obligation with the Lon Nol government while the Americans were not theoretically tied with any personality of the Lon Nol government. Despite being considered as an ally to the Americans, the Lon Nol government only temporarily received aid from the Americans. Thus, we can see that the Lon Nol government was not qualified enough to be considered as an ally to the United States. While the American bombing on the areas which were under the communist control could be seen as preventing the Lon Nol government from falling to the communists, as mentioned by Deac, the American justification of the bombing on Cambodia was to reduce the pressure on the American soldiers in their process of withdrawing from Vietnam. For this reason, we can draw that one of the main reason that the American was supporting the Lon Nol government, could have been to make use of Cambodia for the purpose of buying time to withdraw from the war rather than assisting the Lon Nol government as an ally.

Drawing from such analysis of the relations between Cambodia and American administrations, we can see that America and Cambodia had two distinctive interests. While the Americans were trying to get Cambodia’s support in going against the communists, Cambodia was more concerned of its own domestic politics and the relations with its neighbours. Despite seeing the Prince’s neutrality as the effort to avoid Cambodia from being dragged into the war, the Americans saw neutrality as a hindrance to its effort in exercising its containment policy in Southeast Asia. In this regard, the Prince’s neutrality made the Americans feel unclear of whether the Prince really supported them or their communist opponents. As mentioned by Hallsey, the Prince desperately wanted to keep Cambodia out of the approaching war which his neighbours were already fighting. To ensure the peace for his nation, the Prince had to find the right balance between left and right while at the same time, maintaining the domestic stability within the nation. In contrast, the effort to strike a balance between the United States and the communist bloc had turned Cambodia to be a country that could not be trusted.

As provided by Stephen Walt, the states form alliances in order to prevent stronger powers from dominating them. In addition, as he further mentioned, to form alliance with the dominant power means to put one’s trust in its continued benevolence. On the one hand, a decline in a state’s relative position will lead its allies to opt for neutrality or at worst, defect to the other side. Likewise, in the case of Indochina, the United States were forming the alliance system so that they could contain the communist forces whom they saw to be the threat. Based on the interactions, we can see that the United States was somehow trying to flirt Cambodia into its alliance system. Yet, Sihanouk opted for neutrality since he perceived that the communists would win the war, and China would dominate Asia in the future. What is more, instead of seeing the alliance system as a mean to deter the threat, Sihanouk saw the alliance system that the United States established in Indochina as the threat. As Cambodia’s historical enemies were in the alliance system, Sihanouk preferred neutrality which he believed to be a better option to bring his country to stability. For instance, as being aforementioned, Sihanouk had always pushed the United States to recognize Cambodia’s sovereignty and independence. Thus, Sihanouk chose not to bandwagon with the United States. As mentioned by Hemmer and Katzenstein, after the World War II ended, the United States wanted to organize both the North Atlantic and a Southeast Asian region. Thus, the United States preferred to use bilateral institutional form to achieve such mean. Like NATO, the United States created SEATO as an institutional alliance. For instance, at the Geneva Conference, Cambodia had established the rights that it would be able to join foreign alliance under certain circumstances. While the United States pressed the Prince to join SEATO (the institution created by the U.S to protect Indochina from the communists), Sihanouk rejected the invitation and asked for military aid from Washington instead. The move taken by Sihanouk was perceived by Dulles as the act which weakened SEATO. In addition, Sihanouk’s continual denunciations of SEATO proved that Cambodia was not willing to be an ally to the Americans.

As noted by Shawcross, in the 1950s and the 1960s, the same history had repeated in Cambodia. After the United States started to increase its political and military commitment to fight against the communist regime in Saigon, the American officials found Cambodia to be an obstacle for them as Sihanouk’s refusal to cooperate posed a treat to their effort in controlling South Vietnam. As mentioned by some scholars, America’s failure to accommodate Sihanouk and to preserve diplomatic relations with Cambodia resulted from the actions of the Vietnamese and the Thai governments. While the United States had knowledge that their Vietnamese and Thai allies were taking parts in the plotting against Sihanouk, they failed to put pressure on the two allies to prevent such actions from jeopardizing their relationship with Cambodia. Moreover, the other reason which led to the failure of the United States in establishing the relationship between Cambodia, was because the United States was unable to recognize the importance of local and regional tensions. The United States did not view Sihanouk’s neutrality as mean to escape from being dragged into the war with its neighbours. In this regard, the United States failed to see that Sihanouk was more concerned about the neighbours more than the communist threat as Cambodia’s policy has been directed to ensure its existence and avoid the encroachment from its two powerful neighbours. As noted by Leifer, Sihanouk was aware of the relations between the two antagonists with the United States and the Soviet Union. Thailand and South Vietnam were closely associated with the United States while North Vietnam was aligned with the Soviet Union and China. Thus, the Prince believed that choosing such position would be able to ensure his country’s sovereignty and independence. As mentioned by Hallsey, the Americans would have approached the issue differently if they had a better understanding what Cambodia was concerned about. In addition, we can see that the two countries were not willing to give what it should have taken to improve their relationship to the next level as trust and national interests became the major issues that avoided the leaders of the two countries from accepting one another as an ally.

Based on the analysis and the aforementioned definition of alliance, we can draw that ever since Eisenhower administration to Nixon administration, Cambodia and the United States had never become an ally to one another. Though at one point of the history, Cambodia and the United States almost became an ally, Sihanouk’s rejection to join SEATO had brought an end to the opportunity establish an alliance between the two states. Since Cambodia and the United States had different interests, the relations between the two states could be better fit into an coalition at some points of the history rather than an alliance. Although the relations between Lon Nol and Nixon administration looked more like an alliance, the lack of formal written agreement reflected that lack of willingness by the United States to be an ally to Lon Nol. With this regard, a coalition shall fit better into such context of relationship.


In conclusion, the descriptions of the relations between the United States between the 1950s to the 1970s changed from one administration to one another. Since Cambodia and the United States were guided by different interests during the war period, relations between the two states were unclear. Drawing from the analysis, during the time that Sihanouk was in power, the United States might have perceived Cambodia as a kingdom which could not be trusted. Despite its political and strategic importance, the position that Cambodia was taking made it hard for the Americans to know whether Cambodia was really on their side. Though the Lon Nol government might have been seen as an ally to the United States, theoretically, Lon Nol government was never an ally to the Americans. In addition, one shall not be confused that the military and monetary supports from the American had made the two governments an alliance. Like the other authors had mentioned, Cambodia during the Lon Nol period, was more like a sideshow in which the United States used to maintain a decent interval before pulling out of Vietnam. Thus, such interaction created distrust and yielded undesirable consequences to both sides.


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