Cold War
From dKosopedia
The Cold War is a term that refers to the military buildup and small scale conflicts that occurred between Communist countries and the United States and its allies between the end of World War II (1945) and the fall of the Soviet Union.
The Korean War, Vietnam War, Berlin Airlift, and a various other "hot" military conflicts in the Third World and Greece are all considered to be "Cold War" conflicts.
Its alternative would have been a 'hot" war between the US and the Soviet blocks resulting in the destruction of civilisation if not the whole of humanity.
Other notable events include the the US invasion of Vietnam and the ensuing conflict; the Cuban missile crisis which very nearly led to World War Three; the 'arms race' and the 'space race'; Russian defeat in Afghanistan at the hands of US-supported forces; Gorbachev-inspired reforms and the 'velvet revolutions' in 1989 which toppled most of the Eastern European regimes.