The just war criteria remain an indispensable tool of intellectual analysis for anyone thinking about the morality of military action. If people make a judgement that a particular war is immoral, leaving aside absolute pacifists who reject all resort to force in principle, they will do so on the basis of one or more of the just war criteria, whether or not they consciously appeal to these. It is interesting that the 2004 UN High-Level Panel in discussing the morality of military intervention restates, in almost traditional terms, these traditional just war criteria as being a necessary. Even if force is to be used primarily or solely for human security to protect civilians, as Mary Kaldor argues, it will be necessary to decide who should authorise this force, when it should be used and how its use should be weighed against other considerations.

The use of the just war tradition by Catholic bishops in America and by other Christian denominations there has been criticised for understanding this as a ‘presumption against war’, particularly by George Weigel. Rather, it is, as the late Paul Ramsey used to emphasise, a tool of statecraft primarily for statesmen. It assumes that force must sometimes be used in order to establish international order. There is certainly no absolute presumption against war in it. However, there is an assumption against war in the sense that it must be a last resort and all other options for resolving a conflict peacefully must first have been tried and found wanting.