Cold War, the open yet restricted rivalry that developed after World War II between the United States and the Soviet Union and their respective allies. The Cold War was waged on political, economic, and propaganda fronts and had only limited recourse to weapons. The term was first used by the English writer George Orwell in an article published in 1945 to refer to what he predicted would be a nuclear stalemate between “two or three monstrous super-states, each possessed of a weapon by which millions of people can be wiped out in a few seconds.” It was first used in the United States by the American financier and presidential adviser Bernard Baruch in a speech at the State House in Columbia, South Carolina, in 1947.

A brief treatment of the Cold War follows. For full treatment, see international relations.

Origins of the Cold War

Following the surrender of Nazi Germany in May 1945 near the close of World War II, the uneasy wartime alliance between the United States and Great Britain on the one hand and the Soviet Union on the other began to unravel. By 1948 the Soviets had installed left-wing governments in the countries of eastern Europe that had been liberated by the Red Army. The Americans and the British feared the permanent Soviet domination of eastern Europe and the threat of Soviet-influenced communist parties coming to power in the democracies of western Europe. The Soviets, on the other hand, were determined to maintain control of eastern Europe in order to safeguard against any possible renewed threat from Germany, and they were intent on spreading communism worldwide, largely for ideological reasons. The Cold War had solidified by 1947–48, when U.S. aid provided under the Marshall Plan to western Europe had brought those countries under American influence and the Soviets had installed openly communist regimes in eastern Europe.

The struggle between superpowers

The Cold War reached its peak in 1948–53. In this period the Soviets unsuccessfully blockaded the Western-held sectors of West Berlin (1948–49); the United States and its European allies formed the North Atlantic Treaty Organization (NATO), a unified military command to resist the Soviet presence in Europe (1949); the Soviets exploded their first atomic warhead (1949), thus ending the American monopoly on the atomic bomb; the Chinese communists came to power in mainland China (1949); and the Soviet-supported communist government of North Korea invaded U.S.-supported South Korea in 1950, setting off an indecisive Korean War that lasted until 1953.

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From 1953 to 1957 Cold War tensions relaxed somewhat, largely owing to the death of the longtime Soviet dictator Joseph Stalin in 1953; nevertheless, the standoff remained. A unified military organization among the Soviet-bloc countries, the Warsaw Pact, was formed in 1955; and West Germany was admitted into NATO that same year. Another intense stage of the Cold War was in 1958–62. The United States and the Soviet Union began developing intercontinental ballistic missiles, and in 1962 the Soviets began secretly installing missiles in Cuba that could be used to launch nuclear attacks on U.S. cities. This sparked the Cuban missile crisis (1962), a confrontation that brought the two superpowers to the brink of war before an agreement was reached to withdraw the missiles.

Cuban missile crisisAerial photograph of Medium Range Ballistic Missile (MRBM) Launch Site 1 near San Cristóbal, Cuba, taken on October 25, 1962.U.S. Department of Defense/John F. Kennedy Presidential Library

The Cuban missile crisis showed that neither the United States nor the Soviet Union were ready to use nuclear weapons for fear of the other’s retaliation (and thus of mutual atomic annihilation). The two superpowers soon signed the Nuclear Test-Ban Treaty of 1963, which banned aboveground nuclear weapons testing. But the crisis also hardened the Soviets’ determination never again to be humiliated by their military inferiority, and they began a buildup of both conventional and strategic forces that the United States was forced to match for the next 25 years.