2. Often used to describe what would have happened in the Cold War Era were one side to have attacked the other using nuclear weapons, causing the other side to retaliate, ensuring the nuclear obliteration of most of Asia and North America.
2. Mutually assured destruction never happened in the Cold War -- look around you people; we're living in America, not the movie Cyborg.
2. While this term is specifically used to term the USA and Russia, it may also be applied to China as the latter has built an intercontinental ballistic arsenal that would be deployable if the USA and China ever faced off.
-- Alan Moore, as the voice of Professor Milton Glass, "Dr. Manhattan: Super-Powers and the Superpowers", in Watchmen (DC Comics, 1986)