In contemporary just war theorising the principle of the moral equality of combatants - as found in Walzer's Just and Unjust Wars - has come under intense critical scrutiny. For example, McMahan has persuasively argued for the moral asymmetry of those fighting on the just and unjust sides of a war, reflecting our understanding of cases of justified self-defence. This paper examines the prospect of defending the MEC by appeal to an account grounded in the concept of toleration. Such an account recognises that there is good moral reason to condemn (and prosecute) combatants fighting for the unjust side of a war, but posits countervailing principled reasons to refrain from doing so, despite motive and opportunity – giving it the structure characteristic of toleration. The success of any such argument, then, depends on a defence both of this structure and of the reasons for toleration (and their limits).
