Introduction and Literature Review
On May 4, 1970, hundreds of students congregated on Kent State University's Commons, a popular campus meeting spot, to protest the United States' recent invasion of Cambodia. When the students failed to comply with an order to disperse and instead responded with rocks and shouts of "pigs off campus," Ohio National Guard troops, called in to quell the demonstration, advanced toward the students, firing canisters of tear gas that drove them beyond a hill overlooking the Commons. What happened next remains unclear forty years later, but when the dust settled four students--Allison Krause, Sandra Lee Scheuer, Jeffrey Glenn Miller, and William K. Schroeder--had been fatally shot by the Guardsmen. The Chicago Tribune described the incident as a "scene of unreality ... [one would] expect to see in Viet Nam ... not at a school." (1) The situation was not helped when White House Press Secretary Ronald Ziegler read a tone-deaf statement from President Richard M. Nixon that bemoaned the consequences when "dissent turns to violence." (2) Less than two weeks later, James Earl Green and Phillip Lafayette Gibbs were killed by police during antiwar protests at Jackson State College in Mississippi. Across the country, from the University of Maryland at College Park to Illinois State, and from Columbia University to Williams College, campus disturbances were reported, and thousands converged on Washington for a major protest on May 9. The Nixon administration's ten-day-old invasion of Cambodia had reinvigorated the Vietnam protest movement. (3)
The fallout from the decision to invade Cambodia extended to the halls of government as well. Two hundred and fifty State Department employees signed a statement condemning the invasion. Peace Corps workers seized the organization's headquarters and flew Viet Cong colors from its flagpole. (4) A number of cabinet secretaries expressed their disapproval with the decision to invade Cambodia; Secretary of the Interior Walter Hickel dissented publicly. (5) In the U.S. Senate, John Sherman Cooper (R-KY) and Frank Church (D-ID) introduced an amendment to a military appropriations bill which would cut off funding for any American combat forces operating in Cambodia or Laos after June 30, and bar any bombing of Cambodia that Congress had not approved. Looking back on these events in his memoir, The White House Years, Henry Kissinger, then Nixon's National Security Advisor, wrote that in the weeks following the Cambodian incursion "the very fabric of government was falling apart." (6)
The Cambodian incursion shook the foundations of American democracy to its very core. The repercussions from the decision to invade, which included Kent State, the Cooper-Church Amendment, and a rash of resignations from the National Security Council, speak to how unexpected and, in some ways, unprecedented the invasion was at the time. In the four decades since the tragic events of early May 1970, the Cambodian invasion may have faded from memory, but it remains controversial. Its causes, legality, and its domestic and military consequences remain much debated in the scholarly literature of the Vietnam War, as well as in the memoirs of key government officials, most notably those of Nixon and Kissinger. Many questions regarding the Cambodian invasion remain unresolved. The military historian John M. Shaw writes that:
only a handful [of scholars] have focused on the Cambodian incursion of 1970. Most studies mention it only briefly, describing it chiefly within the context of the resulting domestic uproar against Nixon's 'widening' of the war.... For one of the biggest U.S.-South Vietnamese operations of the war, such dismissive treatment is inappropriate. (7) This study has grown out of a concern over the gap in the literature regarding this controversial topic that this author shares with Shaw. While some authors have explored the run-up to the operation, the scholarly discussion has paid more attention to what happened after the invasion than the circumstances in Cambodia in March and April 1970 that influenced the decision to undertake it. As a result, scholarly treatments of the invasion often focus on the leadership styles and beliefs of Nixon and Kissinger. These studies attribute the genesis of the invasion to the psychological flaws of these two widely-disdained, complicated figures. (8) Other works emphasize the role the military in pushing for a foray into Cambodia as early as the mid-1960s. (9)
This study stresses the radically changed circumstances in Cambodia in early 1970 as the key to understanding the decision to invade that country. Following the March 1970 overthrow of Cambodia's head of state, Prince Norodom Sihanouk, 'the nature of Communist infiltration intensified. This newly precarious political and military situation in Cambodia was exacerbated by declining U.S. troop numbers in South Vietnam and the Nixon administration's desire to extract a favorable settlement from North Vietnam without conceding the survival of a non-Communist South Vietnam, and the attendant military pressure to achieve this goal necessitated. These factors led military and intelligence analysts, together with administration officials, to realize the utility of an invasion to eliminate the Viet Cong/North Vietnamese Army (VC/NVA) sanctuaries along the Ho Chi Minh Trail in Cambodia. Such circumstances, not irrational paranoia or some other psychological issue of either Kissinger or Nixon, would prove decisive in the president's decision to invade Cambodia in late April 1970.
To be sure, the personalities of decision-makers should not be discounted. There is no denying that personality, character, and ideology are of great importance in explaining the introduction of U.S. combat troops in Cambodia, and this study will feature some discussion of these factors. However, it seeks to shift the focus away from Nixon and Kissinger's much-discussed and speculated-upon proclivities and neuroses toward the changing political and military circumstances in Cambodia in March and April 1970. It also places a new emphasis on the strategic framework Nixon and Kissinger applied to Vietnam, and the ways in which the decision to invade Cambodia proved to be rational within that framework. (10) In brief, the coup, along with the Communist push against the new government in Phnom Penh, not only seriously threatened Cambodia's neutrality, but also presented the Nixon administration with its best opportunity to neutralize VC/NVA sanctuaries in Cambodia, which had been a constant source of frustration for the United States throughout the war. Furthermore, the opportunity and the threat presented by the coup was not one which only Nixon and a small group of advisors recognized; it was endorsed by elements in the military, the Central Intelligence Agency (CIA), the White House, and the U.S. Embassy in Saigon.
This does not mean that this study will serve as an apology for the Nixon administration or Nixon himself. Nor will it be a particularly vehement defense against those who criticize the invasion on the grounds that it violated international law or the tragic outcomes it produced both in the United States and Cambodia in the spring of 1970. Rather, it is response to a collection of scholarship and some important works of investigative journalism which have misdiagnosed, or at least partially misunderstood, how the United States found itself in Cambodia. One school of authors, which includes Robert Dallek, Seymour Hersh, and William Shawcross, who have expressed their disapproval of the invasion take issue with the way the Nixon administration seemed to play fast-and-loose with the neutrality and sovereignty of Cambodia, as well as its broader strategic approach toward Vietnam. (11) These authors accuse the Nixon administration of rushing through a secretive and flawed decision-making process leading to an invasion that "had almost nothing to do with the realities of Cambodia." (12) Without the flawed leadership of Nixon and Kissinger, they argue, the military campaign would likely never have taken place. In fact, according to Shawcross, an invasion of Cambodia was a feature of Nixon's foreign policy long before the coup, and would have occurred regardless of the situation on the ground. (13) Each of these authors emphasize Nixon's drinking problems and psychological state, and Kissinger's obsession with shaping military or political policy to explain the Cambodian incursion.
Others, including Shaw, James Willbanks, and Lewis Sorley, place greater emphasis on the Nixon administration's consideration of its own goals, and on the military's perception of the situation in Vietnam, rather than the personal flaws of the key players involved in the decision-making process that resulted in the invasion of Cambodia. These authors point to the United States' ongoing, seemingly at-odds efforts to withdraw from South Vietnam while maintaining a commitment to Vietnamization in the hope of stabilizing Saigon, and the pressures these efforts placed on Washington and the Military Assistance Command, Vietnam (MACV) as the major factors that explain the Cambodian invasion. (14) While this school of thought is valuable in its emphasis on the run-up to the invasion as opposed to its consequences, it consists almost entirely of military histories, and therefore does not provide a comprehensive narrative and analysis of the goings-on in the Nixon administration before the invasion.
Kenton Clymer and Craig Etcheson stand mostly outside of this dichotomy. Their treatments of the invasion are more equivocal and are framed as part of a larger narrative of U.S.-Khmer relations. While Clymer sees the invasion as a deliberate and conscious exercise of presidential power by an "anxious" Nixon, he notes the role the military played in pushing for action, as well as the uncertainty engendered by the constant fluctuation in...