I have been reluctant to criticise Andrew Anthony’s piece on Malcolm Caldwell in The Observer as, in general, I find it to be a great piece of journalism. Despite this, there is one matter that needs to be mentioned. At one point in the article Anthony states:
an American-supported coup put in place the corrupt government of Lon Nol in Phnom Penh.
This is not accurate. The following is taken from pages 61-2 of Wilfred P. Deac’s superb book on the Cambodian War: Road to the Killing Fields: The Cambodian War of 1970-1975 (Texas A&M University Press, 1997):
To the question of whether the United States was behind [the coup], the answer is no. Did Americans have foreknowledge of the event? A qualified yes, because, although some were aware of ongoing agitation, even Cambodian participants did not expect actual deposition of the samdech. Did the United States have contact with anti-Sihanouk elements and encourage them? Yes and no.
“Lon Nol’s coup came as a complete surprise to us,” stated President Nixon, who was enraged that he had received no forewarning from his intelligence community. Henry Kissinger, his assistant for national security affairs, said, “We never encouraged Sihanouk’s overthrow nor knew about it in advance. We did not even grasp its significance for many weeks.” Despite the political shadow subsequently and justifiably cast over both men, there is little reason to doubt their words. Available documents, including contemporary internal memoranda, indicate, as Kissinger said, “that Cambodia was scarcely a high priority concern.” Foremost on the administration agenda – its focus on strategic history-making issues often to the detriment of “lesser” ones – was rapprochement with both the USSR and the PRC. Overthrowing Sihanouk would have worked against this goal. In Southeast Asia, U.S. attention centered on the critical situation in Laos, where the CIA-backed Montagnard forces were facing defeat, and, more important yet, on pulling out of Vietnam. Again, it was not in American interest to upset the status quo. No matter how mercurial Sihanouk was or how much he was distrusted, he had, for the first time in years, adopted a pro-U.S. position.
Robert Dallek adds (Nixon and Kissinger: Partners in Power [Harper Collins, 2007], p.191), Nixon “initially refused to recognize Lon Nol’s government.” He believed that Sihanouk might return to power and “described relations with Lon Nol’s regime as on ‘a temporary basis.’”
Update
It can be added that Steve Heder, in his masterly study, Cambodian Communism and the Vietnamse Model, Volume I: Imitation and Independence, 1930-1975 ([White Lotus Press, 2004], p.156), has also looked into this matter and he concluded that the evidence of CIA involvement in the coup “is not compelling.”