Following the revelations about what had been going on in Iraqi prisons, run by American and British troops, there has been universal and justified condemnation. Moral philosophers will hardly need in the future to invent arguments against the utilitarian justification of torture or to look for examples of inuria in bello.

Amid all the furore, one small but possibly significant phenomenon has been a steady procession of erstwhile supporters of the war, now seeking to distance themselves from the whole operation. Some are now saying that they had been wrong to support it in the first place.

This may indeed be the case. They might indeed have been wrong all along, for a whole variety of reasons, moral and practical. What, though, would be unfortunate would be if the misconduct of one operation meant that the whole question of wars of humanitarian intervention were to disappear from the philosophical and political agenda. Apart from anything else it would seem to blur any distinction between ius ad bellum and ius in bello.

But more important, we still have to consider whether it might ever be morally imperative to invade another country to protect its people, and if so when. Such a consideration may never have been part of the traditional just war doctrine. But that doctrine was formulated in times very different from our own, times when neither communications nor state nor military power were anything like they are to-day.

To put the matter bluntly: should we in the West be ashamed that we did little or nothing in Rwanda in the 1990s, say, even though Western interests were hardly affected by what was going on? We knew well what was going on, and we did nothing as hundreds of thousands were butchered. Would it be right or wrong for a coalition of states (any coalition) to intervene were such a situation to happen again? Or would the high probability that at least some of those the invaders thought they were liberating would come quickly to resent their ‘liberation’ be sufficient to rule out action of the part of those not directly affected?

The sad truth is that we cannot rule out a situation like Rwanda arising again in various parts of the world. Sudan may be on the verge of such a catastrophe even at the time of writing. We need to be prepared philosophically as well as practically.