Following action with the U.S. Navy in the Pacific, where he commanded a PT boat, John F. Kennedy ran successfully for a seat in the U.S. House of Representatives in 1946. He was re-elected twice. In Congress he criticized what he believed to be a weak stand against Communist China. In 1952 he defeated the incumbent Henry Cabot Lodge, Jr., for a seat in the U.S. Senate. Suffering from a back problem, his first years in the Senate were unproductive. While ill, he wrote a book of biographical studies of American political heroes, later published as the Pulitzer Prize-winning Profiles in Courage.

Kennedy was unsuccessful in his attempt for the Democratic vice-presidential nomination in 1956. He won the nomination for president, and narrowly the election, in 1960. Without reliable majorities in the two houses of Congress, Kennedy's domestic programs were stalled. He accepted blame for the failure of the Bay of Pigs invasion of Cuba in 1961. Programs he initiated included the Alliance for Progress and the Peace Corps. His strongest stand involved the Cuban Missile Crisis, when he ordered a naval and air quarantine on shipments of offensive weapons to Cuba. The Soviets backed down. Kennedy was assassinated in Dallas, TX, on November 22, 1963.