9.3 The Cold War

The United Nations, founded in 1945, was meant to keep the peace through cooperation. Its Security Council gave five permanent members (the United States, the Soviet Union, Britain, France and China) a veto, so the organization could act only when the great powers agreed. Very soon they did not.

Each side read the other's actions as aggression. The Soviet Union saw its control of eastern Europe as protection against another invasion from the west. The United States and Britain saw it as the start of communist expansion. In 1946 Churchill described an Iron Curtain dividing Europe, and the American diplomat George Kennan argued that Soviet power must be firmly resisted wherever it pushed outward. This idea became the U.S. policy of containment, stopping communism from spreading beyond where it already ruled.

• Truman Doctrine (March 1947): the United States promised aid to Greece and Turkey and, more broadly, to free peoples resisting outside pressure or armed minorities.
• Marshall Plan (1948): economic aid to Western Europe, which the Soviet bloc refused (9.2).
• Communist coup in Czechoslovakia (February 1948): the last eastern country with a working democracy came under communist control.
• Berlin Blockade and Airlift (June 1948 to May 1949): after the Western powers introduced a new currency in their zones, the Soviets cut off road and rail routes to West Berlin. The United States and Britain flew in food and coal for about 11 months until Stalin lifted the blockade.
• Two Germanys (1949): the Federal Republic of Germany (West) and the German Democratic Republic (East) were created.
• The Soviet atomic bomb (August 1949) ended the U.S. nuclear monopoly; NATO was formed the same year (9.4).

Both sides built hydrogen bombs in the early 1950s and then long-range missiles. The Soviet launch of Sputnik in 1957, the first artificial satellite, showed that Soviet rockets could reach anywhere, and it started the space race. By the 1960s each superpower could destroy the other many times over, a situation called mutually assured destruction (MAD), which made a direct war unthinkable but kept the world in fear.

Berlin remained a flashpoint. Millions of East Germans had fled west through the city, so in August 1961 East Germany built the Berlin Wall, which became the symbol of a divided Europe. In October 1962 the Cuban Missile Crisis, over Soviet missiles in Cuba, brought the world closer to nuclear war than ever before. Afterward the superpowers set up a direct hotline and signed a treaty limiting nuclear tests (1963).

The Cold War was fought by many means besides weapons. Both sides used propaganda: radio stations such as Radio Free Europe broadcast into the East, while Soviet media portrayed the West as imperialist and racist. Spy agencies like the American CIA and the Soviet KGB ran espionage and covert operations, secretly backing friendly governments and undermining hostile ones.

Where the superpowers did fight, they fought through others. In a proxy war, each superpower backs an opposite side in someone else's conflict. Examples include the Korean War (1950–1953), the Vietnam War (U.S. combat troops 1965–1973), the Yom Kippur War (1973), in which the United States backed Israel and the Soviet Union backed Egypt and Syria, and the Soviet war in Afghanistan (1979–1989), where the United States armed Afghan resistance fighters. The superpowers also backed rival sides in civil wars in Africa, such as Angola's, and in Latin America. Newly independent states in Africa and Asia became prizes in the competition (9.9).

In the 1970s tensions eased in a period called détente. West German Chancellor Willy Brandt's Ostpolitik improved relations with the East, the superpowers signed the first Strategic Arms Limitation Treaty (SALT I, 1972), and the Helsinki Accords (1975) accepted Europe's postwar borders while committing all signers to respect human rights. Dissidents in the East later used those human rights promises against their own governments. Détente faded after the Soviet invasion of Afghanistan in 1979, and a new arms buildup followed in the early 1980s, until reforms under Gorbachev ended the Cold War (9.7).