Men o'War.

Warrior Politics: Why Leadership Demands a Pagan Ethos, by Robert D. Kaplan (Random House, 198 pp., $22.95)

Since September 11, America's political and military leaders have had to make many tough moral decisions. How many Afghan civilian casualties would be "acceptable" in waging the war on terror? How cozy should the U.S. become with unsavory regimes in the Middle East, if they could provide key intelligence that might help us nab Osama bin Laden and other terrorist bosses? Should the U.S. use targeted assassination to take out terrorists? For some, even to contemplate measures that would involve civilian casualties, alliances with despots, or assassination is morally compromising; actually to carry them out would put the U.S. on the same level as its fanatical Islamist enemies. A priest's sermon at a Catholic service I attended shortly after September 11 perfectly expressed this moral perfectionism; the U.S. must not respond militarily, he argued, but instead be the "gentle giant."

Robert D. Kaplan, an Atlantic Monthly correspondent and author of several books on international relations, thinks such moral delicacy both naive and immoral. In this lively new book, he argues that America's political leaders, confronted with the stark realities of 21st-century global politics, and entrusted with the safety of those who have elected them, have the moral responsibility to free themselves from what he sees as Judeo-Christian niceties and instead seek guidance from the tough-minded historians and philosophers of pagan antiquity, and those writers and statesmen inspired by them. Kaplan's "warrior" heroes are Homer, Thucydides, Livy, Sun-tzu, Machiavelli, Hobbes, Malthus, America's Founders, and Churchill.

Kaplan never defines his pagan "ethos," but several components of it are clear. First is a tragic sensibility that recognizes the permanence of human evil and political conflict. It was because he possessed in full this tragic sense, gained from years of historical reflection, classical learning, and hard military experience, that Winston Churchill -- a kind of exemplary modern pagan in Kaplan's view -- saw through Hitler from the start, when few others did. Such a realistic worldview, Kaplan adds, would also make American political leaders deeply skeptical of pursuing legal solutions to global conflict -- a permanent temptation for liberal humanitarians, who have long sought such remedies, from the failed Kellogg-Briand Pact banning war after World War I to the multilateralism of the Clinton years. Managing conflict among nations is possible; ending it is not.

If Churchill had no illusions about evil and conflict, he also knew -- and this is a second element of Kaplan's pagan ethos -- that history is not fate: Individuals can move and shape it, even when faced with huge obstacles. "Root causes" do not determine the destiny of man. Kaplan devotes several illuminating pages, heavily indebted to the historian Paul Rahe, to Churchill's extraordinary 1899 book The River War, which describes how, during the late 1890s, colonial Britain used guile, spirit, and force to recapture the Sudan from the Muslim warriors who had briefly conquered it. The genius of Churchill's narrative, Kaplan says, is to show how an "intractable physical and human landscape becomes the obstacle that moral men surmount."

But Churchill also teaches that some humility is vital if political action is to succeed. History may be open to human will, but not every obstacle can be surmounted. In Kaplan's outlook, the political leader must embrace what the French political theorist Raymond Aron called "probabilistic determinism": understanding that human freedom works within certain economic, political, and social constraints. By taking into account such constraints, America's leaders will be better able to use the freedom they possess.

In trying to move and shape history, Kaplan stresses, America's political leaders must be willing to get their hands dirty. Here Machiavelli and Sun-tzu are the best guides. "As Machiavelli says, in an imperfect world men bent on doing good -- and who have responsibility for the welfare of a great many others -- must know occasionally how to be bad, and to savor it." Democratic statesmanship requires a morality of consequences, not intent. Drawing on Sun-tzu, Kaplan observes that such a political morality would justify "every manner of deceit" if it prevented a greater evil like war.

According to this view, moralism has no place in foreign policy. A misplaced emphasis on human rights, for example, can lead to outcomes that actively harm human flourishing. However unjust, the military dictatorship now running Pakistan is preferable to the Islamic militants who might take power through democratic means. The modern media will be "willful and dangerous" enemies of the kind of leadership that accepts that a dictatorship might sometimes be better than a democracy, because the media are politically unaccountable and so can indulge in moral posturing. American statesmen must know how to ignore media moralists.

A final aspect of Kaplan's pagan ethos is a healthy patriotism, as beautifully expressed by the Roman historian Livy, who "shows that the vigor it takes to face our adversaries must ultimately come from pride in our own past and our achievements." Those who undermine American patriotism threaten the nation's future.

The future such an ethos will try to master, Kaplan bleakly predicts, will be full of danger. Darwinian global capitalism is ripping up age- old traditions and spawning terrifying inequalities, dividing the world into a small number of super-bright cosmopolitans, like us, who grow rich from the new world order, and hundreds of millions -- a new "subproletariat" -- who just can't keep up. The unemployed young men of this emerging global underclass, crowded into overpopulated cities and enraged by their poverty, make for a swelling army of potential Islamist terrorists. These new terrorist enemies, Kaplan thinks -- prophetically, since he wrote this book before September 11 -- will be incredibly savage, Homeric "warriors" who will use horrific low-tech weapons to offset our vast technological advantages. Only America will have the power and wealth and civic virtue needed to defeat these resentful warriors and make the world less dangerous -- if, that is, our leaders are sufficiently attuned to the wisdom of his pagan tradition.

What should we make of Kaplan's argument? Much of it is entirely sensible and serves as an important reminder that political reason is something different from interpersonal morality. A government that followed my priest's suggestion to avoid fighting back against the perpetrators of September 11 would encourage future attacks and the loss of more innocent lives. The statesman's chief responsibility is to protect the citizenry.

But Kaplan's paganism isn't without problems. Consider his celebration of Machiavellianism. Why should a political leader "savor" getting his hands dirty? Did Lincoln relish the steps he took to win the Civil War? Shouldn't the proper attitude toward killing civilians or using deceit during wartime be one of haunted necessity? Two of the great Machiavellians of the 20th century, after all, were Stalin and Hitler; surely Kaplan doesn't want to elevate such monsters into moral exemplars. He does admit that an unchecked dirty-hands approach would lead politicians to "drown in cynicism and deceit," but he provides no criteria, other than the "character" of political leaders, to say when it's okay to use Machiavellian tactics and when it's not.

Kaplan's desire to elevate a warrior ethos also leads him to call views pagan that aren't pagan. Kaplan describes America's Founders as pagans, for example, because they designed a republic that takes into account the human propensity for evil. But as Michael Novak shows with overwhelming documentation in his important new book, On Two Wings, what drove most of the Founding Fathers was a Biblical understanding of human sinfulness.

Indeed, from Augustine to Aquinas to Reinhold Niebuhr to contemporary writers like Novak and George Weigel, Christian thinkers, acutely aware of man's fallen nature, have made all the good arguments about the need for force and the permanence of this-worldly conflict that Kaplan attributes to paganism. Yet they have retained a crucial place for a transcendent ought that limits the evil governments can do. Kaplan pays only lip service to Christian just-war theory, and regularly disparages the Judeo-Christian tradition of moral and political reflection. Also, are Machiavelli and Hobbes really part of a pagan tradition? It makes much more sense to describe them, as the political philosopher Leo Strauss did, as proto-moderns.

In addition, Kaplan's reading of where global politics is heading is flawed in crucial ways. His belief that economic globalization is creating a new global subproletariat is simply a myth. In an important recent study, World Bank economists David Dollar and Aart Kraay conclude that the current wave of globalization, beginning around 1980, has actually promoted economic equality. More important, globalization has resulted in a spectacular reduction in world poverty, even in countries, like China, where it has led to greater inequality. World Bank data show that, during the past decade of accelerated globalization, roughly 800 million people escaped poverty. Kaplan's analysis would lead us to oppose globalization as a cause of human suffering, when it is in fact easing lives on an unprecedented scale.

Even if globalization were creating a new pariah class, however, it still wouldn't be breeding terrorism, as Kaplan thinks. Militant Islam has surged in countries with booming economies, like Kuwait. A poor Muslim country like Bangladesh, conversely, isn't a terrorist hotbed. It seems, furthermore, to be relatively well-off, university-educated young men who are most attracted to jihadism. Kaplan sometimes grasps the weakness of the economic determinism that undercuts his main argument about freedom and history. At one point, he observes, "Anyone who assumes that economic incentives determine the future of world politics should read Mein Kampf."

These criticisms aside, Kaplan has written a provocative book. Tough measures and tragic choices will be necessary to win the war on terror, and revisiting Kaplan's preferred political thinkers will hardly lead us astray.