Sunday 22 May 2016

1954-1979: The Wars in China, Cambodia & Vietnam.






Cambodia's Strategic Triangle:
the Long Shadow of the Geneva Conference Over Chinese Foreign Policy.


§1. Introduction.
In politics, bureaucratic mechanisms of action can continue to operate for many years after the decisions of the leaders that set them in motion.  Even in a democracy (with leaders changing every few years), the unstated assumptions defining foreign policy can last much longer than a single administration, and may pass unquestioned from one administration to the next.  In Communist China, where the careers of individual bureaucrats (like Zhou Enlai [周恩來]) could endure for decades, the implicit assumptions whereby policy-goals were formulated could have an even greater power-of-continuity.  This essay addresses one example of this phenomenon, in arguing that the policy shaping the Chinese invasion of Vietnam in 1979 was (in principle) set in motion by China's participation in the Geneva Conventions of 1954: specifically, this paper argues that China's strategic view of Cambodia (and of the unique historical figure, Sihanouk [西哈努克]) were formed at this remarkably-early date (1954–6).  Understanding this reveals the motivations of the leaders and also the bureaucratic mechanisms that would endure for decades as China underwent a seemingly self-contradictory series of policies (fighting against their fellow Communists in Vietnam, and forming a strategic alliance with the United States against the Vietnamese, etc.); these decisions can instead be understood as a consistent expression of the lessons that China (and Zhou Enlai, specifically) learned in Geneva in 1954.



§2. Survey of the Literature.
A survey of the literature must begin with a brief mention of the primary sources: direct statements from Zhou Enali are available in speeches transcribed at the Geneva Conference (e.g., Young, 1968, a book-length collection of primary sources) and in "secret" Communist Party communications, somehow attained by foreign powers and published (e.g., Anon., 1978, with the self-explanatory title: Classified Chinese Communist Documents: A Collection).  These sources are of limited use to this paper, as Zhou Enlai often speaks in a manner that is intentionally enigmatic and provocative:
Our relations with Vietnam, Laos, [and] Cambodia [in 1971] are as those between the front and the rear.  But, for the present, it is not appropriate to overpraise Vietnam; we should treat her as we do the other two nations.  The contradiction among them should be solved by themselves.  Vietnam shows anxiety over Nixon's visit to China.  We have made explanations.  If she cannot figure it out for the moment, let her just watch the development of the truth. 
(Anon., 1978, p. 477, transcribing Zhou from Dec. of 1971)

This could almost be described as a "coded" statement, but sources of this kind are, nevertheless, invaluable (and they can sometimes confirm or invalidate a theoretical claim).



The current generation's (academic) re-evaluation of the history of the Sino-Vietnamese war is represented by (1) Zhang, 2015, a book that offers a new analysis of the causes and nature of the war, with special emphasis on the role (and career) of Deng Xiaoping [鄧小平]; (2) Khoo, 2011, approaches the same conflict with an emphasis, instead, on the Sino-Soviet split, i.e., presenting the Chinese invasion of Vietnam (in 1979) as a proxy-war.  A substantive essay could be written just in contrasting these two, new (book-length) analyses of the subject; however, for the purposes of this paper, it is noteworthy that neither book devotes significant attention to the Geneva agreement (although both do mention it, briefly, on several pages).  (3) Another significant contribution to scholarship (on Sino-Vietnamese relations from 1972–1979) is a collection of nine articles under the editorship of Westad and Quinn-Judge (2006).  One of the differences between these authors (i.e., differentiating Zhang, Khoo and also the authors contributing to this 2006 volume) is the periodization they assign to this history: what was "the turning point" in China's relationship with Vietnam?  The second chapter of this book (by Chen Jian) puts emphasis on 1968–9 (and examines the details of Sino-Vietnamese relations at that time, in the context of China's hostilities against Russia, then verging on open war, including the Zhenbao Island [珍寶島] dispute, etc.), whereas the first chapter (by Lien-Hang T. Nguyen) offers a very different analysis in assigning the turning point to 1971 (when the Vietnamese reacted to the announcement that Nixon would visit Beijing). (Op. Cit., p. 22–23)  Although these may sound like trivial differences (1968 vs. 1971), they are not: the wealth of facts and contradictory information available to historians allows very different political theories to be supported simply by selecting different "flash-points" as explicating the Sino-Vietnamese descent-into-war.

Although the 1979 war has slipped into obscurity, it is even more rare to find new scholarship on Sino-Vietnamese relations in the era of the Geneva Conference.  Calkins, 2013, offers a book-length treatment of precisely this subject, covering 1947 to 1954.  This work draws special attention to tensions between China and Vietnam in an even-more-obscure period of conflict: August 1950 to February 1951.  During this period, China was keeping an eye on Vietnam and Cambodia while, simultaneously, launching its offensive into Korea (Oct. 1950); important conferences took place in Nanning [南寧] in 1951, where Chinese relations with the Vietnamese disintegrated, with Soviet advisers present as witnesses. (Calkins, 2013, p. 78–9)  This sort of observation (as part of a meticulous history of foreign relations between China and Vietnam in this period) adds tremendous depth to our understanding of hostilities between the two countries, and, also, of the attitudes (and apprehensions) that the Chinese would have had prior to the Geneva Conference in 1954.  Waite, 2012, offers a new "global history" of the Geneva Conference, including considerable material on Zhou Enlai's role, although it does not show any significant interest in the friendship between China and Cambodia.

Among the relatively recent sources, I would note the research of Sophie Richardson (2010), presenting new conclusions based on both archival sources and numerous interviews with Chinese Foreign Service employees who served during the era. (Quinn-Judge, 2011, p. 684)  These interviews affirm that Cambodia was much more important to Chinese policy (in this era) than most people appreciate in retrospect: 
Richardson contends that since 1979, the post-Mao Chinese leadership placed Cambodia at the center of China's foreign relations, resulting in Beijing not only delaying normalization of the PRC-USSR and PRC-SRV relations but also "actually compromising both [China's] economic development and territorial security." 
(Zhang, 2015, p. 3)
Although I agree that China's obsession with Cambodia is crucial to understanding foreign policy in this period (and Richardson's thesis would come as a surprise to many scholars, in both East and West, who underestimate Cambodia's significance), I would differ from Richardson in placing the start of this obsession much earlier than 1979.

In surveying the previous literature, Zhang (2015, p. 2) suggests that material prior to the year 2000 be considered in a separate category.  The reason for this seems to be the strength of the Cold War bias up to roughly the year 2000.  Chen (1987) argues in support of Deng Xiaoping's decisions (as "reasonable and sophisticated") in launching the war. (Zhang, 2015, p. 3)  This analysis was published by the Hoover Institution (an anti-Communist, pro-American institution, tightly connected to U.S. Foreign Policy interests during the Cold War), and perhaps reflects the political interests of the time.  Other pre-2000 books on the subject are hampered by the struggle to move beyond the initial stages of news-reporting: e.g., Chang, 1986, is still debating the likelihood that China and Vietnam would resume their hostilities (i.e., that a border war of some kind would ensue), 7 years after the conflict had ended.

§3. How Does the Literature Link 1954 to 1979?
Every significant work on the topic makes some mention of the 1954 Geneva Conference, but they often take an anachronistic view, influenced by the Vietnamese side's (historically-subsequent) regret that they agreed to it, and their resentment that China (and Zhou specifically) had convinced them to sign:
In a discussion with Khmer Rouge leader Ieng Sary on 7 September 1971, [Vietnamese Diplomat Le Duc] stated: "We [the Vietnamese Communists] will always remember the experience of 1954.  Comrade Zhou admitted his mistakes in the Geneva conference of 1954.  Two or three years ago, comrade Mao [毛澤東] did also." […]
The "betrayal at Geneva" idea was later to provide a useful mobilization tool [i.e., propaganda] against the Chinese after the Sino-Vietnamese border war in 1979.
(Khoo, 2011, p. 95–6)

Although this is an important concept to be familiar with, it has had a distorting bias on how the whole period (1954–1979) is understood, i.e., many people interpret the evidence as if historically-subsequent regrets (on the Vietnamese side) had actually shaped the events in 1954:
Since 1979 the Vietnamese Communists have charged that the Chinese delegation at the Geneva Conference, led by Zhou Enlai, compromised with the French at the expense of the Viet Minh… At the time of the settlement, however, the Vietnamese leadership accepted the formula devised at Geneva. […] [In Zhou's negotiations with Ho Chi Minh,] Ho also agreed that the DRV's future relations with Laos and Cambodia would be based on the principles of "peaceful coexistence," which emphasized non-interference in the internal affairs of other countries.
(Calkins, 2013, p. 123)

The same demand that Zhou made, above, for Cambodia to have real independence from Vietnam  (in 1954) would still be the basis for peace negotiations with Deng Xiaoping in the 1980s.  If we can set aside this idea of "betrayal", the continuity of Chinese foreign policy is striking.

The "betrayal at Geneva" idea results in both the dramatization of China's role (with Zhou misrepresented as a compradore) and the dismissal of the substantive content of the agreement: it is a distraction from China's explicit demands for Vietnam to keep their hands off of Cambodia, already articulated in 1954.  The betrayal theme also tends to overlook the question of what the various parties learned from this transaction (i.e., how it may have shaped leaders' objectives and bureaucratic expectations).  Although Vietnam later regretted signing the agreement, and their feeling of betrayal is significant, this should not be allowed to obscure the fact that China presented Vietnam with a set of demands that the Vietnamese did break (and would break repeatedly, including in their interventions in Cambodia immediately before the 1979 war); this is the crucial link from 1954 to 1979, that many scholars are overlooking. 

§4. The Big Triangle and the Small Triangle. 
China's relationship with the United States after the Nixon pact is often described as a strategic triangle.  Although this triangulation of anti-Soviet policy existed on a large scale, China was also involved in a smaller triangle, in trying to preserve Cambodian independence against Vietnam.  Needless to say, these triangles were linked by the Soviet alliance with the Vietnamese Communists (and, thus, China's hostilities against Vietnam were inextricably linked to the Sino-Soviet split).  Although a great deal of attention is paid to the failure of China's friendship with Vietnam, much less attention is paid to the success of China's friendship with Cambodia: the personal friendships between Sihanouk, Mao and Zhou are well-known (attested in photographs, autobiographies, etc.) but the rationale for the political relationship is (prima facie) unclear.  This friendship endured for decades, and continued long after the deaths of both Mao and Zhou, yet nobody could claim that China was supporting Cambodia (or Sihanouk, specifically) for some obvious, cynical gain (e.g., Cambodia did not have oil-fields or gold-mines, etc.).  When did this relationship begin, and what were China's motives at that initial stage of policy-formation?

Joseph Stalin died in 1953, suddenly allowing greater flexibility for Russian foreign-policy-makers, and, at least hypothetically, Mao and Zhou may have felt that they could take more initiative in this period (i.e., acting without Russian approval in creating a foreign-policy strategy for Southeast Asia).  1953, also, was the year that Cambodia received formal independence from France, and this would inevitably lead China to reconsider their relations with Sihanouk's government.  The Geneva Conference introduced Zhou to the fundamental assumption that Cambodia was struggling to preserve its independence not from France, but from Vietnam:
The official Kampuchean delegate representing Sihanouk’s Royal Government to the Geneva Conference, Sam Sary […] sought to secure evacuation of the Vietminh from his country… During the first Indochina War (1946-54), the Battambang province of Kampuchea was practically under the Vietminh control; since 1951 irregular Vietminh forces were being stationed in different parts of Kampuchea.  This was not welcome in Phnom Penh.  Hence, Sam Sary refused to make any concessions to the communist point of view.  He observed that the Kampuchean communists were foreigners who were manipulated by a foreign country, thereby transparently hinting at the Vietnamese.  … A Vietminh invasion of Kampuchea’s Stung Treng province in early 1954 led Phnom Penh to request military aid from the United States.  
(Basu, 1987, p. 5–6)
Implicit in the formulation above is the problem that if the Chinese do not convince the Vietnamese to respect Cambodia's sovereignty, the result will be the U.S. setting up military bases in Cambodia to repel the Vietnamese.  This was a significant fear for China in this period, given the recent experience of the Korean War.  Although it might seem difficult-to-believe that the Soviets or the Chinese would be receptive to the Cambodian point of view (as Sihanouk's government was both monarchist and engaged in a violent struggle against Communists), the optimism of the post-Stalin era and Sihanouk's self-professed status as a socialist of some kind may explain why the Chinese were, in fact, so sympathetic in 1954:
When several rounds of negotiations regarding Kampuchean communist representation failed, the then Soviet Foreign Minister, Molotov, accepted the [Royalist] Kampuchean representative’s proposal that the latter’s country must be given the freedom to ask for foreign military help and, if the circumstances so needed, freedom to allow foreign military bases, and that communist revolutionary groups would not be incorporated into its national life.  Hanoi protested the Soviet decision because it thought that such decision went beyond the acceptable limits of a compromise and would go against communist interests in Kampuchea.  To break this deadlock Molotov and the then British Prime Minister, Anthony Eden, requested China to make the Vietminh agreeable to the aforesaid demand of Kampuchea.  Zhou Enlai then assured Eden that he would persuade the Vietminh to withdraw from Kampuchea and that China would recognise the Kampuchean Royal Government if there were no American bases in Indochina. … Hanoi gave in to Beijing’s persuasion and thus the deadlock was broken.
(Basu, 1987, p. 7–8)
Here we have a very clear strategic triangle, on a small scale, following a sort of syllogistic logic:
• China wants to prevent U.S. military bases in Cambodia.
• Sihanouk's government (already independent from the French) needs guarantees of independence from Vietnam, and will turn to the United States for protection if this is not achieved through diplomatic means (or by Chinese suasion).
• Therefore, it is in China's interest to support Cambodian independence, and to oppose Vietnamese hegemonism. 
As Richardson, 2010, emphasizes throughout her work (and even in its title), 1954 was also the year of China's promulgation of "The Five Principles of Peaceful Coexistence" [和平共處五項原則] as the cornerstone of foreign policy.  Although these principles are primarily remembered with reference to China's relations with India (and the Non-Aligned Nations Movement), it may have also provided a sort of "bedrock assumption" as to why China would treat Cambodian independence so sympathetically at this time.  At Geneva, China demanded that Vietnam both extricate itself from Cambodia's internal affairs, and abide by "The Five Principles"; this concept was probably much more meaningful to the Chinese than it was to the Vietnamese.  Even if Chinese foreign policy treated this concept cynically in a later era, it is reasonable to assume that it was taken seriously in 1954.

§5. Irrational Aspects of Foreign Policy: Friendship and Enmity.
In photographs, the incongruous contrast between Sihanouk (sometimes in Royal costume) and his Communist allies is self-evident.  To some extent, personal friendship eludes political analysis, and Sihanouk's friendships with Zhou and Mao would endure until the Chinese leaders died of old age (with a large portion of Sihanouk's life spent in Beijing).  While biographical material is outside of the scope of this essay, an often-overlooked aspect of both the personal and political dynamics between China and the king was his abdication of the throne in 1955. (Sihanouk, 2004)  The importance of this event is easily forgotten in retrospect, as Sihanouk would eventually regain his royal titles (after several changes in the country's government), but, from the Chinese Communist perspective, the fact that he renounced his Royal status (to become a commoner) may have been a powerful demonstration of his sincerity as a socialist of some kind.  Whereas Communism had elevated men like Mao and Stalin to positions resembling an emperor, Sihanouk had made the principled decision to renounce his position of enormous political and religious power in Cambodia, to stand for election as a commoner.

Although he is often referred to as a  king throughout this period, the fact is that when Sihanouk attended the Bandung conference (and spent time with Zhou face-to-face) he was not a king.  When Sihanouk visited Beijing in February of 1956, he already had a well-established friendship with Zhou, and had been articulating his own socialist beliefs for several years.  Although the basis for personal friendship can never be reduced to a simple, political formula, it seems reasonable to assign significance to Sihanouk's abdication (at this time): part of the explanation for why the Chinese Communists embraced this "class enemy", was, perhaps, because he had himself renounced his class status.

There is a prolix literature devoted to China's seemingly irrational enmity toward Vietnam in this period (all of the sources surveyed comment on it, or analyze it under various headings, including racism, rivalry, historical experience, etc.).  However, (1) it is much more difficult to explain the friendship with Cambodia than it is to explain the antipathy toward Vietnam, and (2) if we fully understand China's friendship with Cambodia, and the commitments made in 1954, this diminishes the significance of the "irrational" hatred for Vietnam (i.e., the latter ceases to be relied upon to explain why decisions were made, or why the 1979 war happened, etc.).  Inasmuch as we understand China's prior commitment to Cambodia (and their repeated disappointment with Vietnamese conduct toward Cambodia), less and less of the foreign-policy behavior (1954–1979) needs to be explained by irrational factors.  Conversely, China's friendship with Sihanouk may itself be an example of an irrational factor: if Zhou and Sihanouk had disliked (or distrusted) each-other, the whole history of this period would have been very different.

§6. The Small Triangle: China, Cambodia and Vietnam.
At this time (1956) the friendship was formalized with promises of financial aid, and China overtly committed itself to supporting Sihanouk's government against both Vietnamese aggression and Cambodia's (indigenous) Communist rebels. (Basu, 1987, p. 17)  This set of policy-decisions would prove to be amazingly durable: they basically did not change during Zhou Enlai's lifetime, nor during the Nixon pact, nor when Deng Xiaoping inherited the leadership.  China continued this basic formula (following this set of assumptions) continuously from 1954 to 1979: seeing the problem in terms of (1) China's commitment to support Cambodian independence against Vietnamese aggression, and (2) Vietnam's failure to fulfill their vow to abide by the Five Principles (as quoted, above, from Calkins, 2013, p. 123).

Even in the subsequent period, from 1979 to 1989, China's position (in negotiations with Vietnam) remained remarkably consistent: 
[…] [In the 1980s, China continued to insist that] Hanoi needed to confess its mistaken policy toward China and withdraw from Cambodia before Sino-Vietnamese relations would improve.  Deng remained adamant on this point.  When Hanoi sought rapprochement with Beijing in 1989, the new Chinese leadership continued Deng's policy, even asking his endorsement for their negotiations with the Vietnamese leadership.  Consequently, after more than 10 years of conflict and the loss of many Vietnamese lives and resources, Hanoi had to agree to terms that were virtually dictated by Deng Xiaoping.
(Zhang, 2015, p. 217)
We may expand on this observation: in 1989, China was not merely pursuing the same policy goals as in 1979, but the same goals as in 1954.  In 1989, Sihanouk was still living in Beijing (most of the time), and waiting for China to return him to power (either as the figurehead, or as the actual leader).  Despite the tremendous changes in the policy-environment (including the decline of the Russian threat in the 1980s, etc.), the underlying assumptions and objectives of China's foreign policy had remained the same.

§5. Verification: the Chinese and American Perspectives. 
Although the shift in perspective proposed by this essay may seem to be a minor nuance, it has tremendous implications, in part because of the intersection between the two strategic triangles, described above.  Although the Cambodian Communists had relied on support from Vietnam throughout their entire history (militarily, logistically, etc.), they made the fateful decision to stab the Vietnamese in the back at their Third Party Conference (in the Cardamom mountains) in September of 1971; at this conference, they resolved to gradually purge all pro-Vietnamese elements from within their ranks, and to eventually wage war against Vietnam. (Bizot, 2004, p. 113)  This decision (closely resembling the Chinese decision to purge all pro-Soviet members of the Communist Party, many years earlier) coincides (in timing) with the Kissinger-Zhou negotiations, and is linked to it, in terms of the logic of the strategic triangle:
…in July 1971, when the then US national security advisor Henry Kissinger made his historic visit to China, he found the Chinese leaders worried about the prospect of a united Vietnam following US withdrawal from Indochina.  In fact, it seemed to him that China was more concerned about a united Vietnam than the issue of Taiwan.  China even agreed to help in maintaining the then pro-US regime in Saigon as a condition for the withdrawal of US troops from Taiwan.  Even an agreement was reached between the United States and China for installing a coalition government in Saigon with Vietcong participation which would look up to Beijing rather than Moscow.
(Basu, p. 22–23)
Can these claims be verified with reference to Zhou Enlai's own perspective?  Can they be verified from Nixon's perspective?  In broad outlines, the answer is yes.

We have a (so-called) "secret document" from Zhou, dated to March of 1973, reflecting at length on China's changing strategy in Vietnam (in precisely this era of the emerging strategic triangle).  Here we read, from Zhou's own pen:
The Soviet revisionists will intensify economic aid to the Vietnamese people after the Vietnamese war [against the Americans] comes to an end to countervail our influence in Vietnam.  The struggle afterwards will be complicated and acute. […] 
They [i.e., the Soviets] contend with us about this point mainly with the intent of vying with us for exerting influence over Vietnam. […] 
If war arises in Vietnam, would the U.S. armies send hundreds of thousands of men to Vietnam as they did before?  It seems unlikely. […] 
The current situation in Cambodia is also good.  The Lon Nol regime now controls only a small piece of land, and moreover, it seems that the Americans do not very much appreciate this president.  Lately the attitude of Prince Sihanouk has been tough and resolute.  Man is subject to change, and a change toward progress is good.  The peace in Indochina is temporary; no one is sleeping. […] 
In future, the Soviet revisionists will direct their strategic deployment at the whole world sphere, confronting not only the U.S. but also us.  While they both struggle against and collude with the U.S., they maintain completely antagonistic relations with us.  This is the essence of the problem.
That we oppose two superpowers is a slogan.  The essence lies principally in opposition against the most threatening enemy, Soviet revisionist social-imperialism.  We have a distinct understanding of this, and so does the U.S.
(Anon., 1978, p. 486–9)
This statement from Zhou affirms, in broad outlines, that China would indeed continue to support Sihanouk, accepting U.S. support in a struggle against Soviet influence in both Cambodia and Vietnam.  The possibility of this struggle requiring warfare seems to already be appreciated (the peace in Indochina is temporary, he says, and the Americans will not intervene (against China?) if there is another war in Vietnam, etc.).

In turning to Nixon's perspective, this approach allows us to understand the change in U.S. foreign policy, when the Americans switched to supporting the Khmer Rouge (in concert with China) after the Mao-Nixon pact. (Mazard, 2009)  Nixon believed that "all our diplomatic efforts to end the civil war in Cambodia were absolutely dependent on the continuation of our bombing[,]" (Nixon, p. 179) apparently because the U.S. understood China's objectives, and were using the bombing as leverage in negotiations (to form an anti-Soviet pact with China that would include an anti-Vietnamese component, thus ending the civil war in Cambodia).  For China, the ensuing pact (sealed in "mid-June" of 1973, according to Nixon himself) would be, again, remarkably consistent with their strategy since 1954:
Chinese Prime Minister Zhou Enlai also wanted to prevent a North Vietnamese victory in Indochina. China wanted closer relations with the United States to counter increasing hostility from the Soviet Union.  Therefore, it was directly contrary to Peking’s interests for Moscow’s clients in Hanoi either to achieve hegemony in Indochina… We had the elements necessary to strike a deal.  We had significant influence over Lon Nol.  China could pull the strings of the Cambodian Communists.  Sihanouk… the nominal head of the opposition forces, would listen to Zhou’s council.  We soon put together a plan.  Lon Nol would give Sihanouk a limited role in the government in exchange for an end to the fighting. Sihanouk and Khmer Rouge forces [i.e., then on the same side] would settle the war in exchange for an end to our bombing.
(Nixon, 1985, p. 176–7)
One aspect of this quotation from Nixon that seems to be intentionally misleading is the phrase, "settle the war".  Nixon must have known that this meant that the (pro-China) Khmer Rouge would win the war, replacing Lon Nol (and it was, indeed, as the head of a Khmer Rouge government that Sihanouk briefly had "a limited role in the government", not on the Lon Nol side).

Meanwhile, China needed to find new (anti-Vietnamese) allies within Cambodia, after the Lon Nol coup d'état displaced Sihanouk (March 18th, 1970).  This was a coup that took place while Sihanouk was in Beijing (where he could comfortably remain, and where he lived a considerable portion of the remainder of his life), and he responded to the news by declaring a united front with the Communists; however, this implicitly meant a union with pro-Maoist, anti-Soviet Communists, who had not been (heretofore) organized into a separate militia from the Soviet-supported Communists.  From this point forward, Sihanouk's role as a Chinese-sponsored figurehead is overt (and continues until the 1990s).  Although the Cambodian Communists had always been divided into factions, the anti-Vietnamese faction (adhering to the Third Party Congress resolution, aforementioned) was now willing to demonstrate its eagerness for Beijing's support with a body-count:
[Over 1,000 Cambodian communists who had fled to Vietnam circa 1954 (and were educated there since then) begin returning to join the Khmer Rouge struggle,] …but they soon found themselves the objects of extermination by some of the local Communists.  The latter, or at least one faction, had as early as 1971 decided that the Vietnamese could not be trusted and were potential enemies, and by 1973 were perhaps putting out the word that the Vietnamese were the principal enemy. 
(Vickery, 1999, p. 215)
Broadly speaking, these factional transformations within the Cambodian Communist Party (who had to temporarily accept their former enemy, Sihanouk, as their nominal leader, because he was sponsored by China, etc.) are all connected to the strategic triangles described, and the plans set out in the quotations above from both Nixon and Zhou.

§5.  Conclusions.
Whereas many authors have struggled to explain the turning-point when China switched from supporting Communist Vietnam to opposing it, the view proposed by this essay is (instead) that the priority Zhou Enlai gave to Cambodian independence in 1954 remained a constant feature of Chinese foreign policy until the 1990s.  In other words, Chinese Foreign Policy did not undergo a sudden transformation in 1979: almost every other country involved (including the United States, etc.) had dramatically changed their foreign policy in this theater, but China's objectives and understanding of the situation had remained remarkably consistent.

In many state-systems (not only Communist ones), policy-decisions become ossified: the rational motives for the policy may be forgotten, as the assumptions of the leaders (at a specific point in time) become durable aspects of the daily operations of a professional bureaucracy.  At the Geneva Conference in 1954, I would suggest that Zhou Enlai learned a set of strategic assumptions about Southeast Asia, and he then became even more confident in these assumptions after meeting Sihanouk at the Bandung Conference (1955), and then receiving Sihanouk as an honored guest in Beijing soon thereafter (1956).  I would neither characterize these assumptions as rational nor irrational: they include matters as diverse as Maoist ideology (the Five Principles being "in fashion" at that time), the vague distrust of the Vietnamese (partly stemming from the 1951 negotiations in Nanning, among numerous other factors), the potential for new initiatives presented by the (then-recent) death of Stalin, and even personal friendship with Sihanouk (in the context of Cambodia's recent liberation from France, the King's abdication of the throne, etc.).  In this context, the Sino-Soviet split itself has relatively little explanatory power: the Chinese continued to pursue the same objectives (in defense of Cambodia against Vietnam) at all times after 1954, regardless of whether or not relations with the Soviets were tense or relaxed at the given moment.  China's position was the same in 1956, 1968, and in 1985: in very different periods of Sino-Soviet rivalry, this policy did not change.

China's obsession with Cambodia ("actually compromising both [China's] economic development and territorial security", Zhang, 2015, p. 3) remained constant after the fear of U.S. bases in Cambodia had become irrelevant, and after the idealistic belief in the "The Five Principles of Peaceful Coexistence" had faded from memory.  This is a powerful example of how bureaucratic mechanisms and institutional attitudes can maintain a policy-goal over many decades, with very little reconsideration as to whether or not the objectives were really desirable (for the leaders, for the Chinese people, or even for the Cambodian people) after an initial stage of policy-formation.  Obversely, U.S. policy in Cambodia provides another stunning example of the same problem, as the U.S. would continue to jointly support this proxy-war (against Vietnam), supporting the Khmer Rouge (via the border with Thailand, etc.) from the late-1970s to the 1990s.  For non-specialists, this remains one of the most puzzling (even incomprehensible) periods of Cold War politics, as the Chinese ended up fighting against the Vietnamese Communists, and the Americans ended up supporting some of the most notorious Communists in the world (the Pol Pot faction, a.k.a. the Khmer Rouge).



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