In the preface of the 2006 edition ofJust and Unjust Wars, Michael Walzer makes an important distinction between, on the one hand, “measures short of war,” such as imposing no-fly zones, pinpoint air/missile strikes, and CIA operations, and on the other, “actual warfare,” typified by a ground invasion or a large-scale bombing campaign. Even if the former are, technically speaking, acts of war according to international law, he proffers that “it is common sense to recognize that they are very different (...) from war.” While they all involve “the use of force,” Walzer distinguishes between the level of force used: the former, being more limited in scope, lack the “unpredictable and often catastrophic consequences” of a “full-scale attack.” Walzer calls the ethical framework governing these measuresjus ad vim, and he applies it to state-sponsored uses of force against both state and nonstate actors outside a state's territory that fall short of the quantum and duration associated with traditional warfare. Compared to acts of war,jus ad vimactions present diminished risk to one's own troops, have a destructive outcome that is more predictable and smaller in scale, severely curtail the risk of civilian casualties, and entail a lower economic and military burden. These factors makejus ad vimactions nominally easier for statesmen to justify compared to conventional warfare, though this does not necessarily mean these actions are morally legitimate or that they do not have potentially nefarious consequences. (shrink)

This article contributes to the debate among just war theorists about the ethics of using armed drones in the war on terror. If violence of this kind is to be effectively restrained, it is necessary first to establish an understanding of its nature. Because it is difficult to conceptualize drone-based violence as war, there is concern that such violence is thus not captured by the traditional jus ad bellum framework. Drone strikes probably do not constitute a law enforcement practice, so (...) the peacetime ethics of criminal justice do not apply either. One possible solution is to develop and apply a legitimization framework of jus ad vim in which vim is “force short of war,” although this depends upon a vim–bellum distinction being a sustainable one. Moving beyond discussion of these three alternative concepts of drone-based violence, the article suggests a fourth—vis perpetua —and explores the ethical implications thereof. As a form of violence that presents no physical risk to individual users of force, a program of drone strikes poses a moral problem if it is intended to continue indefinitely, leading to the systematic endangerment of innocents without the eventual promise of peace. (shrink)

A just cause for war is a type of wrong that may make those responsible for it morally liable to military attack as a means of preventing or rectifying it. This claim has implications that conflict with assumptions of the current theory of just war.