The "equalizer" of the Old West made it possible for either man to kill the other; it did not assure that both would be killed. The tense consequences of this weapon system can be seen on TV almost any night. The advantage of shooting first aggravates any incentive to shoot. As the survivor might put it, "He was about to kill me in self-defense, so I had to kill him in self-defense." Or, "He, thinking I was about to kill him in self-defense, was about to kill me in self-defense, so I had to kill him in self-defense." But if both were assured of living long enough to shoot back with unimpaired aim, there would be no advantage in jumping the gun and little reason to fear that the other would try it.

DEFINE: This introduces the 'equalizer' concept — how equal-payload weapons create first-strike incentive rather than deterrence, a key game-theory mechanism. Builds on: "Deterrence depends on surviving retaliation capacity, not raw destruction."

Thomas C. Schelling, The Strategy of Conflict, loc. 530