Chapter 21 : The Cold War After World War II, Europe was divided into the Eastern bloc, dominated by the Soviet Union, and the Western bloc, tied to the United States. The Marshall Plan helped Western European countries rebuild their economies. Under the Truman Doctrine, the United States aided countries threatened by Communist takeovers. To unite and maintain control of its territories, the Soviets created the Warsaw Pact. Western nations formed the NATO alliance for their own mutual defense. The international tension during the cold war affected American society in the 1950s, when concern arose about Communist influences in government and other public arenas. During the 1960s there were advances in civil rights. The Vietnam War, however, divided American society and led many to question America's military role in the world's trouble spots.