A suitcase nuke is a tactical nuclear weapon which uses, or is portable enough that it could use, a suitcase as its delivery method. Synonyms include suitcase bomb, backpack nuke, mini-nuke, and pocket nuke.
Thus far, only the United States and the Soviet Union/Russian Federation are known to have possessed nuclear weapons programs developed and funded well enough to manufacture miniaturized nuclear weapons. Both the United States and the Soviet Union have acknowledged producing nuclear weapons small enough to be carried in specially-designed backpacks during the Cold War, but neither have ever made public the existence or development of weapons small enough to fit into a normal-sized suitcase or briefcase. It has also been reported that Israel has produced nuclear warheads small enough to fit into a suitcase.
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