Answer: Mutually Assured Destruction - a military strategy put in place to help prevent nuclear warfare.
Explanation: Mutually Assured Destruction, also known as MAD, is a doctrine of military strategy and national security policy in which a full-scale use of weapons by two or more opposing sides would cause the complete annihilation of both the attacker and the defender. It shaped the nuclear arms race in a drastic way, as it helped to remind both parties that neither side could expect to survive a full-scale nuclear exchange as a functioning state.