2007 Reports

Strategic militarization, deterrence and wars

Jackson, Matthew O.; Morelli, Massimo

We study countries choosing armament levels and then whether or not to go to war. We show that if the costs of war are not overly high or low, then all equilibria must involve "dove," "hawk," and "deterrent" strategies and the probability of war is positive (but less than one) in any given period. Wars are between countries with differing armament levels and the frequency of wars is tempered by the presence of armament levels that are expressly chosen for their deterrent properties. As the probability of winning a war becomes more reactive to increased armament, the frequency of wars decreases. Finally, as it becomes increasingly possible to negotiate a credible settlement, the probability of peace increases, but the variance of armament levels increases and war becomes increasingly likely when negotiation is not available. This matches observed patterns in the data over time.