There are allegations that the United States (U.S.) directly armed the Khmer Rouge during the Cambodian–Vietnamese War in order to weaken the influence of Vietnam and the Soviet Union in Southeast Asia. It is not disputed that the United States encouraged the government of China to provide military training and support for the Khmer Rouge and that the United States voted for the Khmer Rouge to remain the official representative of the country in the United Nations even after 1979 when the Khmer Rouge was mostly deposed by Vietnam and ruled just a small part of the country.[1][2][3]

Additional alleged U.S. actions that benefited the Khmer Rouge range from tolerating Chinese and Thai aid to the organization (Henry Kissinger) to, according to Michael Haas, directly arming the Khmer Rouge. The U.S. government officially denies these claims, and Nate Thayer defended U.S. policy, arguing that little, if any, American aid actually reached the Khmer Rouge. However, it is not disputed that the U.S. voted for the Khmer Rouge, and later, for the Coalition Government of Democratic Kampuchea (CGDK), which was dominated by the Khmer Rouge, to retain Cambodia‘s United Nations (UN) seat until 1982 and 1991, respectively.