Limiting the Killing in War: Military Necessity and the St. Petersburg Assumption

This article suggests that the best available normative framework for guiding conduct in war rests on categories that do not echo the terms of an individual rights-based morality, but acknowledge the impossibility of rendering warfare fully morally justified. Avoiding the undue moralization of conduct in war is an imperative for a normative framework that strives to actually give behavioral guidance to combatants, most of whom will inevitably be ignorant of the moral status of the individuals they encounter on the battlefield and will often be uncertain or mistaken about the justice of their own cause. We identify the requirement of military necessity, applied on the basis of what we refer to as the “St. Petersburg assumption”, as the main principle according to which a combatant should act, regardless of which side or in which battlefield encounter she finds herself. This pragmatic normative framework enjoys moral traction for three reasons: first, in the circumstances of war it protects human life to a certain extent; second, it makes no false claims about the moral justification of individual conduct in combat operations; and, third, it fulfills morally important functions of law. However, the criterion of military necessity interpreted on the basis of the St. Petersburg assumption does not directly replicate fundamental moral prescriptions about the preservation of individual rights.