Threshold Constraints and Laws of War

Abstract

The laws of armed conflict forge a balance between deontological humanitarian concerns on one hand, and consequentialist military-advantage concerns on the other hand. Yet the literature provides inadequate theoretical foundations for the balances these rules make at a structural level. In this paper, I explain how the standard humanitarian account and the first-wave economic account cannot alone explain the diversity of rules and principles observed in the formal doctrine and in state practice. States’ revealed preference for norms fleshing out those “minimum standards” can not be brushed aside as mere “behavioral regularities.” Many of these minimum standards are the result of purely instrumental coordination, since all belligerents are better off with full compliance under conditions of transparency and effective enforcement. But recognizing that states sometimes act for non-instrumental reasons supplements rather than falsifies claims that states act rationally under other circumstances. By adopting and deploying recent advances in law and economics that seek to bridge the gap between consequentialist and deontological moral theories, I show how the complex system of the laws of war are the product of both kinds of concerns. This working paper applies the threshold constraint framework to an emerging class of problems in the laws of armed conflict related to cyberwarfare. Uncertainty, risk-shifting, threshold-constraint concerns, and cost-reduction preferences play important roles in shaping law-of-armed-conflict rules, which in turn constrain and channel the tactical options states can select in carrying out armed conflict. These concerns also have institutional-design effects when states are uncertain about how technological progress will change battlefield conduct. This draft ends by explaining and understanding how states might seek to change those rules in light of anticipated (and even unknown) changes in battlefield technology.