Of all the contributions Christian tradition has made to moral discourse regarding public policy and the behavior of nations, perhaps none has enjoyed such influence as the doctrine of the "just war." First articulated by Plato and Aristotle in antiquity, it was later united with a Christian theological worldview in the fifth century by St. Augustine in his magisterial "The City of God." Augustine developed the theory in part as a response to a pastoral concern: is it ever morally permissible for a Christian to participate directly in armed conflict? For the first three centuries, the official stance of the church had been a nearly unanimous "no." Following the teachings of Jesus' "Sermon on the Mount," virtually all the early church fathers advocated pacifism as the moral standard for the church.It was therefore a somewhat surprising when Augustine worked out a different position, based in large part on his paradoxical understanding of the human condition. According to that perspective, war could be understood as both the result of, and at times the remedy for, human sin. Augustine's position might be summarized like this (to paraphrase theologian Reinhold Niebhur): Man's inclination to injustice makes war inevitable; but man's inclination to justice makes war at times necessary.If sin compels human beings to acts of aggression, barbarity, and injustice, human decency may compel us to meet such acts with a countervailing force for justice and peace. For those ends alone, said Augustine, war may at times be required to vindicate justice and therefore considered to be compatible with Christian morality. Augustine's position reflected the church's new status after Roman Emperor Constantine converted to Christianity. Suddenly championed by the world's dominant power, the church was forced to rethink its relation to the political sphere.The doctrine of just war has persisted as a moral touchstone through all the intervening centuries, a testament to its resilience as an ethical formulation. War has undergone sweeping changes, but nations and statesmen--even where Christianity isn't embraced--still use the theory to frame moral imperatives.But applying just-war principles to concrete situations rarely, if ever, leads to self-evident conclusions. Criteria developed centuries ago, when war was conducted largely by mercenary forces in hand-to-hand combat, does not translate easily to modern warfare, with its vast array of lethal instruments, weapons of mass destruction, and impersonal war-fighting techniques.

Furthermore, pacifists on the left and so-called "realists" on the right regard the doctrine with suspicion. Christian pacifism pointedly asks whether any principle that justifies violence, especially the conditions of modern warfare, could be consistent with any of the major sacred traditions, let alone the teachings of Jesus.

"Realists," meanwhile, scoff at the very notion that war, as an extension of the political agenda of the state, can be placed under any moral constraint at all. War, once engaged, takes on a life of its own. The only imperative is to achieve victory as quickly and efficiently as possible. This is the logic of "total war," and usually implies that war itself legitimizes the use of any means to accomplish its ends.

Just-war doctrine stubbornly holds the middle ground. It argues that lethal force may at times be morally necessary, but only while observing the strictest tests of moral constraint.

It may be, however, that just war has become too malleable to be the moral center it has been. It has outlived its usefulness, and must be updated to address an entirely different set of historical and political realities like those we currently face in Iraq. A brief review:Just cause: For nearly two years, members of the Bush Administration have sought to rally support from the American people and our allies for an invasion of Iraq. We have been invited to believe that the principal objective of an invasion will be to disarm a dangerous tyrant; at other times that the chief aim is "regime change"--to oust Saddam Hussein and his government and rid the Middle East of a dangerous leader and rescue the Iraqi people. The United States and its allies could then establish a democratic state in its place that could be a showcase throughout the Arab world.At other times the president said attacking Iraq is necessary to protect American citizens from further terrorist attacks.
(The strategy appears to be working. Though the administration disavows a direct connection between Hussein and the attacks of Sept. 11, The Nation's William Greider cite a recent survey indicating that 42 percent of Americans believe that Hussein was personally responsible for the events of Sept. 11-a truly Orwellian manipulation of public opinion). All of the goals cited above are worthy, and based on the definition of just cause. But every so often we glimpse less idealistic motives that cannot be justified under the traditional conditions of a just cause. There are, for example, the motives hinted at in the vision of the so-called "New American Century Project," which argued that the United States should establish hegemony as the only legitimate superpower. In this scenario, Iraq is but the first act of a larger drama, a demonstration project.A last resort: President Bush has repeatedly assured the American people and the world that the United States will attack Iraq only as a "last resort"--another device meant to place a war within a just-war framework. It's more accurate to say that the United States has been at war with Iraq since 1991. We've maintained "no-fly zones," bombed air-defense systems and levied economic sanctions that have severely deprived the country of resources, food, and medical supplies.The present campaign began with a belligerent case for aggressive action against Iraq, if necessary by unilateral action by the United States. It's not quite plausible to claim at this point that this war is a measure of last resort