Abstract

Proportionality has long been considered a pillar of just war theory, requiring that the goods achieved in an action outweigh the collateral harms it causes. In this article, I argue that the in bello principle of proportionality cannot serve its intended function of limiting the destructiveness of actions during war. I illustrate the features of war that make the in bello proportionality constraint not merely impossible to follow, but perhaps even self-defeating. I conclude by suggesting ways in which theorists and policymakers concerned with justice in war might attempt to respond to this dilemma.