For the United States of America, 1945 to 1964 was a time of high economic growth and general prosperity. It was also a time of confrontation as the capitalist United States and its allies politically opposed the Soviet Union and other communist countries; the Cold War had begun. African Americans united and organized, and a triumph of the Civil Rights Movement ended Jim Crow segregation in the South. Further laws were passed that made discrimination illegal and provided federal oversight to guarantee voting rights.
Early in the period, an active foreign policy was pursued to assist Western Europe and Asia recover from the devastation of World War II. The Marshall Plan helped Western Europe rebuild from wartime devastation. The main American goal was to contain the expansion of Communism, which was controlled by the Soviet Union until China broke away about 1960. An arms race escalated through increasingly powerful nuclear weapons. The Soviets formed the Warsaw Pact of European satellites to oppose the American-led North Atlantic Treaty Organization (NATO) alliance. The U.S. fought a bloody, inconclusive war in Korea and was escalating the war in Vietnam as the period ended. The Communists took power in Cuba, and when the USSR sent in nuclear missiles to defend it, the Cuban Missile Crisis of 1962 was triggered with the U.S., the most dangerous point of the era.
On the domestic front, after a short transition, the economy grew rapidly, with widespread prosperity, rising wages, and the movement of most of the remaining farmers to the towns and cities. Politically, the era was dominated by liberal Democrats who held together the New Deal Coalition: Harry Truman (1945–53), John F. Kennedy (1961–63) and Lyndon Johnson (1963–69). Republican Dwight D. Eisenhower (1953–61) was a moderate who did not attempt to reverse New Deal programs such as regulation of business and support for labor unions; he expanded Social Security and built the interstate highway system. For most of the period, the Democrats controlled Congress; however, they were usually unable to pass as much liberal legislation as they had hoped because of the power of the Conservative Coalition. The Liberal coalition took control of Congress after Kennedy's assassination in 1963, and launched the Great Society.