Morally Heterogeneous Wars

According to “epistemic-based contingent pacifism” a) there are virtually no wars which we know to be just, and b) it is morally impermissible to wage a war unless we know that the war is just. Thus it follows that there is no war which we are morally permitted to wage. The first claim (a) seems to follow from widespread disagreement among just war theorists over which wars, historically, have been just. I will argue, however, that a source of our inability to confidently distinguish just from unjust wars lies in how we evaluate “morally heterogeneous” wars—i.e., wars with just and unjust aims. Specifically, the practice of reaching a univocal evaluation of a morally heterogeneous war as a whole by aggregating the evaluations of that war’s just and unjust aims is wrongheaded, because it undermines the action-guiding character of jus ad bellum. We ought instead to adopt what I call the “disaggregate approach” to jus ad bellum, according to which we evaluate the various aims of a war individually, without aggregating them into an evaluation of the war as a whole. Adopting this approach will eliminate a source of our disagreement over which wars have been just, and will ipso fact eliminate a basis for epistemic-based contingent pacifism.