An Assessment of the Merits of Selective Nuclear Proliferation

We assume that in a conflict between a nation with a nuclear capability and one without, the conflict may become nuclear, while, in a conflict between two nuclear powers, the conflict is unlikely to become nuclear by reason of fear of retaliation. Then, as the number of nations with nuclear weapons increases, the chance of bilateral conflict becoming nuclear initially increases and then decreases to zero when all nations are nuclearly armed. Empirical evidence suggests that nuclear deterrence does in fact work in the way the model assumes. We set forth an expected utility model for initiating conflict when nuclear weapons are held by both sides, by one side, and by neither side. While there are dangers in proliferation, these dangers may not be as great as dangers of asymmetry in nuclear power.