Mutually Assured Destruction (MAD)

The doctrine that emerged once both sides could destroy the other regardless of who attacked first. Each side maintained enough nuclear weapons (in silos, on submarines, and on bombers) to survive a first strike and still deliver a devastating retaliation. The result was a kind of stability: neither side could profit from striking first because retaliation was certain. MAD was a deliberately terrifying doctrine that nonetheless prevented nuclear war between the superpowers for forty years.