1972 in the Vietnam War the number of air raids against North Vietnam during all of 1971. Prime Minister Lon Nol declared President of Cambodia. Unlike the former Cambodian leader, Norodom Sihanouk, Lon Nol was a U.S. ally. The U.S. 101st Airborne Division left South Vietnam, the last U.S. ground combat division to be withdrawn from South Vietnam. The Khmer Rouge bombarded with artillery Phnom Penh, the capital city of Cambodia, killing more than 100 civilians. This was the heaviest attack on Phnom Penh since the Cambodian Civil War began in 1970. The United States boycotted peace negotiations in Paris with the North Vietnamese, citing
Anglo-Thai Peace Treaty which clause undercut the authority of Pridi Banomyong's government. After its enactment, the United States and Britain restored diplomatic relations with Thailand on 5 January. The next day a general election was held. After the treaty, the United States lent $10,000,000 to Thailand for the reconstruction of her transportation network, heavily damaged by American bombing. Thailand joined the United Nations on 16 December 1946. A separate Australian–Thai Peace Treaty, required by the Australian declaration of war of 2 March 1942 and the adoption of the Statute of Westminster, was signed on 3 April 1946. Anglo-Thai Peace Treaty The Anglo-Thai Peace