The calculus of deterrence

Bruce M. Russett

pp. 36-52

in: Harvey Starr (ed), Bruce M. Russett, Berlin, Springer, 2015

Abstract

A persistent problem for American political and military planners has been the question of how to defend "third areas." How can a major power make credible an intent to defend a smaller ally from attack by another major power? Simply making an explicit promise to defend an ally, whether that promise is embodied in a formal treaty or merely in a unilateral declaration, is not sufficient. There have been too many instances when 'solemn oaths' were forgotten in the moment of crisis. On the other hand, more than once a major power has taken up arms to defend a nation with whom it had ties appreciably less binding than a formal commitment. If a deterrer is to be firm, the prospective gains from a successful policy of firmness must be greater, when weighted by the probability of success and discounted by the cost and probability of war, than the losses from retreat.