The theory of just war may go back to Augustine. But its modern herald is Michael Walzer, who in 1977 published his book Just and Unjust Wars (Basic Books). Maybe you read it in a college course, as by now tens (and tens) of thousands of students have. Maybe you participated in a "just war" discussion, informed or uninformed, around a dinner table. In any case, it is one of the key controversies of the age and Walzer, who writes frequently for TNR, has stayed with the subject as more and more wars of terror break the rules and terrorists challenge their opponents' very right to do anything about it.

But it's not only terrorists who challenge these rights. More importantly, it's the self-appointed moralists in the institutions of the United Nations and the NGOs, like Human Rights Watch and Amnesty International, who are ready to condemn the disciplined and restrained response to haphazard war. On Tuesday, a factotum of the U.N. questioned the legality the American use of drones in pursuit of the Taliban. All this is done with full understanding that our targets never respect humane limitations on the practice of war. Never. Can you imagine Hamas laying down guide marks for what you may or may not do in an attack on Israel. In any case, they don't even make a pretense of doing so.

In an essay published during the spring, Walzer confronted the harsh criticisms of Israel in Gaza and the U.S. in Afghanistan using "just war" theory. The essay, titled "Responsibility and Proportionality in State and Non-State Wars," set about protecting the moral integrity of his argument of a quarter century ago and defending it against its abusers and distorters.

Read it, please.

And while we're into deep stuff, here's an alert. In the next print issue of The New Republic (and also online) we will be publishing an article by Moshe Halbertal, who has also written here previously, that confronts in a sober manner the Goldstone report. I believe this essay by Halbertal will be a turning point in the whole argument. Moshe is one of Israel's most learned philosophers and ethicists (forgive me, I hate the word), a professor at the Hebrew University of Jerusalem and at N.Y.U. Law School.