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 The U.S. 101st Airborne Division left South Vietnam, the last U.S. ground combat division to be withdrawn from South Vietnam.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
Treaty of Alexandropol The latter treaty was further ratified as the Treaty of Kars, signed by the Grand National Assembly of Turkey and, at Soviet Russia's insistence, the three (now Soviet) republics of Armenia, Georgia, and Azerbaijan. Treaty of Alexandropol The Treaty of Alexandropol (; ) was a peace treaty between the First Republic of Armenia and the Grand National Assembly of Turkey ending the Turkish-Armenian War that had begun on 12 September 1920 with an invasion of Armenia by Turkish forces led by Kazim Karabekir. It was signed by the Armenian Foreign Minister Alexander Khatisyan in the early hours of 3 December