Just War Theory and the Last of Last Resort

Abstract

The last resort criterion has a hallowed place in the just war theory tradition. Many leading just war theory scholars accept it as a jus ad bellum requirement and some powerful politicians reference it. While there are several versions of last resort, many take it to mean that peaceful options that have a reasonable chance of achieving a just cause must be exhausted before the use of force is permissible. Its justification is straightforward and commonsensical: war is terrible, inevitably results in the deaths of numerous innocents and destruction of their property, and thus should be avoided whenever possible. I argue that last resort should be dropped from the just war tradition because its inclusion in the just war tradition can result in a greater number of harms to innocents than if the precept did not exist. What should matter morally is the severity and numbers of harms inflicted on innocents, not whether those harms are inflicted violently or nonviolently. I suggest that in the context of achieving a just cause, the only actions that are permissible are those that are likely to inflict the fewest morally weighted harms and that meet the other just war theory precepts (excluding last resort). Three accounts of last resort do not permit this, whereas while a fourth does, it is redundant with an important account of the jus ad bellum proportionality precept. Thus violent policies may be preferable in some rare circumstances to nonviolent alternatives such as non-targeted sanctions and negotiations because nonviolent policies sometimes are more likely to foreseeably and avoidably result in far greater harms to innocents than violent options.