Catching up on Cambodian history as we make our way to Phnom Penh, I came across some interesting historical context for the current squabble over Preah Vihar temple. The temple is mentioned in John Tully’s A Short History of Cambodia, during a discussion of King Sihanouk’s nonaligned policy in the 1950’s:
Another running sore was the issue of Preah Vihar, an Angkorean temple on the border that was claimed by both Thailand and Cambodia (and eventually awarded to Cambodia by the World Court at The Hague in 1962). While the hardline anti-communist rulers in Bangkok and Saigon scarcely needed encouragement, Sihanouk suspected with good reason that the United States was egging them on and said that if Washington chose it could call them off. He stated publicly that US policy was unjust and ‘dangerous for peace in South-east Asia’ and moved further towards diplomatic rapprochement with the communist countries.
In short, it seems that the U.S. encouraged Thai claims on the Temple in order to bully Sihanouk to abandon his policy of neutrality during the Cold War, but the policy (like much U.S. foreign policy) backfired, pushing Sihanouk closer to the Communists.