A post-war or postwar period is the interval immediately following the end of a war. The term usually refers to a varying period of time after World War II, which ended in 1945. A post-war period can become an interwar period or interbellum, when a war between the same parties resumes at a later date (such as the period between World War I and World War II). By contrast, a post-war period marks the cessation of armed conflict entirely. Aftermath of World War II The term "post-war" can have different meanings in different countries and refer to a period determined by local considerations based on the effect of the war there. Some examples of post-war events are in chronological order: The Cold War (1947–1991) Cold War The Cold War was a geopolitical conflict between the capitalist and liberal democratic United States of America, the authoritarian and Communist Marxist–Leninist Union of Soviet Socialist Republics, and their respective allies: NATO and the Western Bloc for the United States, and the Warsaw Pact and the Eastern Bloc for the Soviet Union. Although both sides did not fight each other directly, both engaged through various proxy wars. At the height of the cold war, both superpowers manufactured and deployed thousands of nuclear weapons to target each other's key economic, military, and political centers. Each superpower's buildup and demonstration of nuclear strike capabilities lead to an unofficial military doctrine known as mutually assured destruction (MAD). The doctrine of MAD prompted leaders on both sides to believe that victory following a full-scale nuclear exchange was simply impossible as the destruction on both sides would be insurmountable. Towards the end of the Cold War, a period of détente culminated in the easing of tensions, bans on nuclear testing, and the destruction of various quantities of nuclear stockpiles. The Cold War began to come to an end in 1989 with the overthrow of Communist governments across Eastern Europe in the Revolutions of 1989 which was followed shortly after by the collapse of the Soviet Union in 1991, leaving the United States the world's sole superpower.