The United States and Russia continue to rely on mutually assured destruction to deter nuclear war, despite the fact that it has come close to failing multiple times, both during the Cold War and after.

Was mutually assured destruction successful?

Neither side will attack the other with their nuclear weapons because both sides are guaranteed to be totally destroyed in the conflict. ... To many, mutually assured destruction helped prevent the Cold War from turning hot; to others, it is the most ludicrous theory humanity ever put into full-scale practice.

Is mutually assured destruction possible?

Mutually Assured Destruction acknowledged there could be no victor in a nuclear war. Neither nation could attack the other without suffering catastrophic loss from an unstoppable counter-attack. ... And they installed missiles with nuclear warheads in submarines, which could surface and attack with little warning.