Doctrine & strategy
Second Strike
The retaliatory nuclear capability remaining after absorbing an opponent's first strike — the foundation of deterrence under MAD.
Second-strike survivability is achieved through redundancy and concealment: hardened ICBM silos that can withstand near-misses, ballistic-missile submarines patrolling the oceans, and dispersed strategic bombers. The submarine leg is generally considered the most survivable.
Related terms
First Strike
A nuclear attack intended to disarm an opponent before they can retaliate, by destroying their nuclear forces, command, and control.
MAD (Mutually Assured Destruction)
A Cold War strategic doctrine in which two or more nuclear-armed adversaries each possess sufficient retaliatory capability that any nuclear attack would result in their own destruction.
SLBM (Submarine-Launched Ballistic Missile)
A ballistic missile launched from a submerged submarine, providing a survivable second-strike nuclear capability.
Nuclear Triad
A three-pronged nuclear force structure consisting of land-based ICBMs, submarine-launched ballistic missiles (SLBMs), and strategic bombers.