The United States won the 20th century. It became, as the journalist Henry Luce had prophesied, "the American Century."
By the end of the 1990s -- victorious in two world wars, emerging triumphant from the long, twilight struggle with the Soviet Union -- the United States had achieved a position of unrivaled strength.
As they entered the new millennium, Americans saw little reason to doubt that this era of American ascendance would continue indefinitely. They interpreted the nation's global preeminence as evidence of a providentially ordained design, unfolding according to plan. They took it for granted that the juggernaut of democratic capitalism was destined to sweep the world. That the emerging age of globalization would be compatible with American values and interests seemed certain.
Atop this new order, the United States would preside, unchallenged, secure in the knowledge of its good intentions, its republican virtues intact.
The horrific events of Sept. 11, 2001, demolished these sunny assumptions. Developments since that day -- in particular the ever-expanding dimensions of President Bush's "war on terror" -- have raised progressively more troubling questions about the implications of American primacy and the costs required to maintain it.
In this regard, the effort underway to overthrow Saddam Hussein marks a decisive turn. This war should finally clear away the underbrush of myth, obfuscation and willful denial thus far preventing Americans from seeing the momentous changes, now well advanced, in their own thinking about military power and the use of force.
Disclaimers issued by the White House notwithstanding, this war has not been thrust upon us. We have chosen it. That choice -- made by Bush but endorsed by both houses of Congress and supported by the majority of the American people -- reveals much.
By going to war out of a concern for what Hussein might do in the future, the United States has embraced a doctrine of preventive war. By initiating hostilities without explicit United Nations sanction and despite fierce opposition abroad, it has shown that when it comes to using force, the world's sole superpower insists upon absolute freedom of action. Coming 12 years after a prior war with Iraq inaugurated an outburst of U.S. military activism -- with Somalia, Haiti, Bosnia, Kosovo and Afghanistan being just a few of the highlights -- this latest intervention makes one point unmistakably clear: The United States no longer views force as something to be used reluctantly or as a last resort.
There is great irony in this, of course. Our nation was created in the first great anti-imperial revolution. The traditional narrative of our history teaches that our greatness was thrust upon us, that we did not want to sit at center stage in world affairs but that we were drawn there reluctantly, contrary to our traditions and preferences. One hundred years ago, the U.S. was a peripheral continental power with limited influence over world affairs. But wickedness in its various guises -- imperial Spain in 1898, followed by imperial Germany two decades later and eventually by the totalitarian ideologies of Hitler and Stalin -- forced our hands repeatedly. We were a reluctant superpower.
True or false, that narrative no longer holds; the fact is that force, today, has emerged as the preferred instrument of American statecraft in the eyes of policymakers and taxpayers alike. Military might is no longer a necessary evil; entrusted to American hands, it has become invaluable. Thus, as a matter of policy -- one to which Republicans and Democrats alike subscribe -- the United States is committed to maintaining its present military supremacy in perpetuity.
With this aim in mind, the Pentagon gauges its requirements not according to the constitutional mandate of providing "for the common defense." Global power projection, not protecting the homeland, dictates the size and capabilities of U.S. forces and justifies a defense budget dwarfing that of the next 10 largest military powers combined. That might qualify as an astonishing fact, had not Americans long since come to view it as part of the natural order.
Nor do those in authority view this well-honed and immensely versatile asset as a treasure to be carefully husbanded. Thus the Bush administration, like the Clinton administration, calls on its forces not only to win wars but also to succor the afflicted, keep the peace and repair broken nations. More broadly, policymakers today charge the armed services with "shaping the environment" -- bureaucratese for nudging others into conformity with American values.
There is a word for this. It's called militarism.
Although spared the classic Teutonic symptoms -- among other things, we prefer cheering the troops on from afar to actually donning a uniform -- Americans have succumbed to a strain of that disease. The present war against Iraq -- justified in part by preposterous expectations that, having delivered Iraqis from their oppressor, the United States will bring liberal democracy to Iraq and then all the Arab world -- makes this unmistakable.
Seduced by images of war rendered antiseptically precise, we have lost our bearings. We have deluded ourselves into believing that the best hope of safety and security lies in dispatching the cadre of military professionals whom we proclaim to be "our best and brightest" on a mad undertaking to transform the world -- or, if need be, to conquer it.
In Iraq, President Bush has opened up yet another front in his war against evil. Committed, we must win. But the long march to Baghdad should give Americans pause: Exactly where is this road leading us?
Andrew J. Bacevich teaches international relations at Boston University and is the author of "American Empire: The Realities and Consequences of U.S. Diplomacy" (Harvard University Press 2002).