I did not expect to be the focus of Henry Shue's argument about what liberalism does or doesn't permit with regard to weapons of mass destruction. I suppose that the argument of Just and Unjust Wars is in some sense a liberal argument, though it relies so heavily on Catholic theory and Jewish anxiety that perhaps it isn't best read as Shue has read it. Until very recently, liberal political theorists took little interest in war; they were concerned with domestic society (which was represented as an escape from war) and then with international cooperation. The effort to outlaw war among states as it had been outlawed among individuals strikes me as the typical liberal response to the threat of aggression: Treat war as a crime, and deal with it by summoning the global police. The continuing relevance of just war theory is a consequence of the failure (so far, at least) of this liberal project.

So Shue's reading of just war as a liberal doctrine strikes me as a reconstructive effort. But I think that it is a good effort, picking up important features of the doctrine, not only in my version of it. And he reads my version with wonderful sympathy and generosity – more than I can muster on my own behalf after all these years. I doubt that I can rise to his challenge, which focuses in careful detail on the idea of “supreme emergency” and denies its relevance to questions of deterrence.