Deterrence Theory
How the theory of nuclear deterrence evolved, the logic of mutually assured destruction, and why deterrence remains both essential and deeply contested.
The Logic of MAD
Nuclear deterrence is the theory that nuclear weapons prevent war because the costs of nuclear conflict are so catastrophic that no rational leader would initiate one. The most extreme form is Mutually Assured Destruction (MAD): when two adversaries both possess enough nuclear weapons to survive a first strike and deliver a devastating retaliatory blow, neither has an incentive to attack. The stability of MAD rests on the paradox that safety comes from vulnerability, both sides must remain vulnerable to retaliation for deterrence to hold.
Deterrence theory was formalized during the Cold War by strategists like Bernard Brodie, Herman Kahn, Thomas Schelling, and Albert Wohlstetter. Brodie wrote in 1946 that 'thus far the chief purpose of our military establishment has been to win wars. From now on its chief purpose must be to avert them.' Schelling's work on coercive bargaining and the 'threat that leaves something to chance' influenced how nuclear crises were managed. Kahn's 'On Thermonuclear War' controversially argued that nuclear war was thinkable and survivable, an analysis that disturbed many but influenced defense planners.