The web site of Sen. Bob Smith, a Republican who opposes the use of force in Kosovo and is running for his party's presidential nomination announces his home state, New Hampshire's slogan: "Live free or die: there are worse evils than death." Specifically, the worse evils are dishonor and disgrace. These are the most important issues that hang in the balance with NATO's armed forces led by the U.S. now engaged in combat.

The alliance's aerial bombardment campaign aims to destroy a Serbian dictator's means of terrorizing innocent civilian populations which he has done from Slovenia in the north in 1991, to Bosnia further south from 1992 until 1995, and for the past year, with growing ferocity in Kosovo. Failure to accomplish the administration's and NATO's stated goal of protecting the innocent ethnic Albanian population of Kosovo against further brutality would be disgraceful and dishonorable, no matter whether, how, or under which circumstances President Clinton may attempt to redefine the struggle, and perhaps declare victory in order to avoid having to use ground forces.

That the president may choose this ignominious course is clear from his years of hollow threats against Saddam Hussein, and subsequent decision following several days of an air campaign to declare victory and abandon any serious effort to depose Saddam Hussein. The air attack on Iraq last year was not a victory. Nor does calling a horse's tail his leg make it so. Such "victories" convince no one of anything except that the United States is incapable of military action to support a purposeful foreign policy.

It is, as each hour passes, increasingly clear that only ground forces can sweep Kosovo of the Serbs. Their military and police forces are unarguably engaged in the most repulsive acts of wholesale barbarism to be seen on the European continent since World War II. If the U.S.-led NATO alliance cannot find the will to place troops on the ground and stop the humanitarian disaster now in the making, the rest of the world including friends and most dangerously such hostile and perhaps nuclear-armed states as North Korea will rightly ask whether we have the will to defend any of our allies. Measuring our resolve besides North Korea are China, Iran, and Osama bin Laden who are deeply interested to learn the evolving post-Cold War character of American foreign policy.

The stakes for the United States in Kosovo are not exclusively humanitarian. Two American presidents, George Bush and Bill Clinton, warned Mr. Milosevic against the brutal policy that he has carried out there for the past year. It is bad for any nation's foreign policy to be seen as a series of bluffs. This encourages others to test us and discover what they can get away with, a particularly bad development when missiles and weapons of mass destruction are proliferating. There is also a serious strategic question riding on America's will to commit ground forces to Kosovo: Will the peace that now holds in Europe following a century of conflict and near conflict hold? The past 500 years have seen two major political-military problems on the continent.

The first has been the great-power competition that characterized northern European statecraft since the medieval Wars of the Roses and has at various times enmeshed all the powers north of the Alps. A century of American involvement, two hot wars, and one cold one has put this competition to rest - for now.

The other problem - ethnic and religious strife - is centered in southern Europe - the Balkans. And today, as 80 years ago, the northern powers and some southern ones are tied to their Balkan favorites: France conceivably and Russia surely to Serbia, Germany to Croatia, Greece and Turkey to their co-religionists. Mr. Milosevic's systematic policy of exploiting ethnic, nationalist, and religious tensions threatens to engage these outside powers and thus to endanger the successful result of a century of American effort to nourish democracy and peace in Europe. Destroying Mr. Milosevic -or at a minimum his military -covers our great investment in Europe this century.

It would have been better if preventing a humanitarian catastrophe in Kosovo and restricting Mr. Milosevic's predatory attacks on others in the region could have been achieved by diplomacy. It would have been better if air strikes alone could have accomplished the same objectives. Wishing, however, will do nothing.

The NATO air strikes were launched more than a week ago, and it is clear from fleeing women and children's stories that a large-scale butchery is under way in Kosovo. America's credibility as a great power is now being tested. The United States should put troops on the ground in Kosovo as soon as possible: Their mission should be to stop the killing of innocent civilians, destroy the Serb forces in the province, and drive those who flee back into Serbia. It is highly unlikely that enemy forces will be able to conduct successful guerilla operations against our forces: With ethnic Albanians still the overwhelming majority of the population, it is difficult to imagine a less favorable environment for an enemy to conduct a campaign that depends on blending in with the surroundings.

It is difficult to imagine that the Serbs will want to take on NATO ground forces in a thunderous frontal assault composed of M-1 Abrams tanks, Bradley fighting vehicles, multiple launch rocket systems, Hellfire missile-carrying Apache attack helicopters and supported by uncontested, withering air superiority. They will retreat, just as they did before the Slovenian military in 1991 when Milosevic attacked Slovenia.

But remember the key point. Success for NATO means putting an end to the killing, destroying as much as possible of the Serbian war machine, and establishing a perimeter that will protect Kosovo against more butchery.

And if, as Mr. Clinton warned on Tuesday, the United States does indeed recognize Kosovo's claim to independence as a sovereign state, such a force will be needed until the new country can defend itself. Alternatively, the president should consider removing Mr. Milosevic from power by force thus saving the Balkans from more grief and himself and his successors from the predicament we are still in with Saddam Hussein, a confrontation that is far from over - but could have been.

Failure means continuation of the slaughter and a spread of Mr. Milosevic's brutality into Montenegro and Macedonia. It means demonstrating to the world that the word of two American presidents is not to be trusted. It means a serious and perhaps fatal blow to the NATO alliance on which Central Europe's new democracies have staked their future. And ultimately, it means a serious threat to the success of a century of America's hard work and sacrifice in Europe.

We must not fail.

Seth Cropsey is a fellow at the American Enterprise Institute and an officer in the Naval Reserve. He was deputy undersecretary of the Navy in the Reagan and Bush administrations.