Difficult to define exactly, but it's not the actual *name* of a situation or doctrine. Rather, it describes the outcome of a given action in the circumstances:
In the case of the US and USSR, their shared determination to retaliate to an attack by the other - given the size of their nuclear arsenals - would've assured mutual destruction.
by Richter September 20, 2003
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The outrightly suicidal strategy of nations protecting themselves from nuclear (or, in more recent days, chemical or biological) attack by preparing enough weapons to reduce the attacking country to rubble even as they are themselves wiped out.

Basically, if you're going to be screwed over, make sure the rest of the world is, too.
During the Cold War, the US and the USSR built massive stockpiles of nuclear weapons while following a strategy of mutually assured destruction
by Sparky August 31, 2003
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The almost certain scenario that would occur after nuclear war. It says that the opposing forces would be utterly anihilated, leaving the Earth an uninhabitable, radioactive wasteland.
The only result of nuclear war, Mr. President, is mutually assured destruction.
by ZephyrAnima August 31, 2003
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(MAD) The Cold War strategic doctrine which made all-out nuclear war the only possibility for war between the super-power blocs (US & USSR). Like it or not (and who would?), it worked, at least in preventing the use nuclear weapons in war.
by lazarus51 September 1, 2003
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A Cold War idea that neither the U.S. or the U.S.S.R. would use nuclear weapons on the other, knowing attack would lead to a mutually devatating counterattack.
by card law September 2, 2003
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a stalemate in a war where both (or more) sides have wordweapons of mass destruction/word.
by Anonymous September 11, 2003
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Where two guys face each other, wanking off, and try to have both ejaculates collide in mid-air, thus averting catastrophe.
Shall we save the world again tomorrow, Bill?

...from mutually assured destruction
by Big Pawel April 20, 2008
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