Role of Nuclear Weapons in NATO Security

NATO remains a collective security alliance whose purpose, as embodied in Article 5 of the North Atlantic Treaty, is to defend the territorial integrity of all of its member states. To do so, NATO maintains military capabilities (1) to deter any attack and, in the event deterrence fails, either (2) to defeat such an attack if it occurs or (3) to convince the aggressor government that it has miscalculated, that the costs of war far exceed any possible gains, and that the aggressor should cease its attack and withdraw immediately from NATO territory.