Mutually Assured Destruction
MAD
A military doctrine holding that when two adversaries each possess enough destructive power to annihilate the other, neither side will strike first — because doing so guarantees their own destruction in retaliation.
Origin
The doctrine emerged during the Cold War as the United States and Soviet Union amassed nuclear arsenals through the 1950s. Mathematician John von Neumann, a pioneer of game theory and chairman of the ICBM Committee, helped formalize the strategic logic. The memorable acronym "MAD" was coined by military analyst Donald Brennan as a deliberate critique — he considered the strategy insane. Secretary of Defense Robert McNamara became its most prominent advocate during the 1960s.
Everyday Use
Two business partners each hold damaging information about the other, so neither leaks it. Two countries with nuclear arsenals avoid war because the cost would be total. MAD shows up anywhere the threat of mutual ruin keeps a tense peace — from geopolitics to playground standoffs to corporate negotiations.