Mutually Assured Destruction, or (MAD), was coined in reference to a doctrine of military strategy and national security policy in which a use of high-yield weapons of mass destruction by two opposing sides would effectively result in the complete, utter and irrevocable annihilation of both the attacker and the defender, becoming thus a war that has no victory nor any armistice, but only effective reciprocal destruction. An enemy will not dare to launch a first strike because the other side can and likely will retaliate in equal manner, effectively ending civilization on earth.
The strategy is effectively a form of Nash equilibrium in which neither side, once armed, has any incentive to disarm thereafter.
Sources: Wikipedia, Roosevelt Institute Campus Network, RSOPerator.
Have you stumbled upon a prepper term that has left you scratching your head over its meaning? If so, let us know about it here.