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All this talk about a possible US and/or Israeli preventive war against Iran got me wondering about the historical record concerning the conflict behavior of states after they acquired nuclear weapons.  Does the rate at which states are involved in serious international disputes tend to go up, down, or see no change after they get the bomb?

Advocates of preventive war on Iran like Matthew Kroenig expect Iran to become much more aggressive if it gets nukes.  “Proliferation optimists” like Ken Waltz, by contrast, argue that we have repeatedly expected terrible things from nuclear-armed adversaries but repeatedly found, if anything, the opposite to be the case.  For example, both the Soviets and the US contemplated preventive strikes to prevent Mao from getting...