highly sensitive topic in Thailand today. The king was succeeded by his younger brother, Bhumibol Adulyadej. In August Pridi was forced to resign amid suspicion that he had been involved in the regicide. Without his leadership, the civilian government foundered, and in November 1947 the army, its confidence restored after the debacle of 1945, seized power. After an interim Khuang-headed government, in April 1948 the army brought Phibun back from exile and made him prime minister. Pridi, in turn, was driven into exile, eventually settling in Beijing as a guest of the PRC. Phibun's return to power coincided with the onset of the Cold War and the establishment of a communist regime in North Vietnam. He soon won the support of the United Nations. Once again political opponents were arrested and tried, and some were executed. During this time, several of the key figures in the wartime Free Thai underground, including Thawin Udom, Thawi Thawethikul, Chan Bunnak, and Tiang Sirikhanth, were eliminated in extra-legal fashion by the Thai police, run by Phibun's ruthless associate Phao Sriyanond. There were attempted counter-coups by Pridi supporters in 1948, 1949, and 1951, the second leading to heavy fighting between the army and navy before Phibun emerged victorious. In the navy's 1951 attempt, popularly known as the Manhattan Coup, Phibun was nearly killed when the ship where he was held hostage was bombed by the pro-government air force. Although nominally a constitutional monarchy, Thailand was ruled by a series of military governments, most prominently led by Phibun, interspersed with brief periods of democracy. Thailand took part in the Korean War. Communist Party of Thailand guerrilla forces operated inside the country from the early-1960s to 1987. They included 12,000 full-time fighters at the peak of movement, but never posed a serious threat to the state. By 1955 Phibun was losing his leading position in the army to younger rivals led by Field Marshal Sarit Thanarat and General Thanom Kittikachorn, the Sarit's army staged a bloodless coup on 17 September 1957, ending Phibun's career for good. The coup beginning a long tradition of US-backed military regimes in Thailand. Thanom became prime minister until 1958, then yielded his place to Sarit, the real head of the regime. Sarit held power until his death in 1963, when Thanom again took the lead. Thailand during the Indochina wars and communist insurgency The regimes of Sarit and Thanom were strongly supported