The Cold War
The roughly 45-year geopolitical confrontation between the United States and the Soviet Union, fought through proxy wars, espionage, and the arms race rather than direct combat.
Origin
Conventional dates: 1947 (Truman Doctrine) to 1991 (Soviet collapse). Both sides built enormous nuclear arsenals and held them in mutual deterrence — 'mutually assured destruction,' MAD. Proxy hot wars in Korea, Vietnam, Afghanistan, Angola, Central America. Key crises: the Berlin Blockade (1948), the Cuban Missile Crisis (October 1962, the closest the world came to nuclear war), the construction (1961) and fall (1989) of the Berlin Wall. The Iron Curtain divided Europe; the world divided into First, Second, and Third Worlds. The 1991 USSR dissolution ended it without a shot fired between the principals.
Modern usage
Reference point for every subsequent great-power rivalry. 'A new Cold War' is the standard framing for current US-China tension. 'Cold-War mentality' is now used in Chinese state media. The James Bond films, le Carré novels, and the entire spy-thriller genre run on it. 'MAD,' 'arms race,' 'proxy war,' 'détente,' 'sphere of influence' are all naturalized vocabulary.
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