and Stable Deterrence
War is not a mere act of policy, but a true political instrument .... The political object is the goal, war is the means of reaching it, and means can never be considered in isolation from their purpose.
Karl von Clausewitz
In Soviet—American experiences of the past decades, the stability of deterrence in crisis (no sudden escalation to nuclear war) and the relative stability of the arms race (few very sharp, large increases in spending) both depended on the fact that neither side had a first-strike capability. Existing technology meant that neither side's nuclear retaliatory forces were highly vulnerable. If either side had been highly vulnerable, the situation would have been quite different. It also would have been different if both sides' forces had been vulnerable, that is, if the matter of who struck first could have made a very great difference in the outcome of a war. Knowledge of that could have been highly dangerous in a crisis and also would have fueled the arms race.
The difference between first- and second-strike capability is crucial to understanding both the arms race and deterrence theory. A first-strike capability implies that one could attack and