WHICH U.S.-LED MILITARY ACTION of the past decade will set the pattern for the current Balkan war? As the United States moves closer to committing ground troops, the choice is stark.

In 1989, American military intervention in Panama destroyed a dictator's ability to threaten U.S. personnel in the Canal Zone. And it achieved the larger objective of ending an obnoxious regime by removing its head, Manuel Noriega. Panama hasn't turned into a model Jeffersonian republic, but the problems Noriega caused disappeared with his arrest.

Iraq is another story. In 1991, a U.S.-led coalition secured the military objective of driving the Iraqi army from Kuwait. Regrettably, however, it did not achieve the strategic objective of halting the endless mischief of Saddam Hussein, who remains a source of growing problems today. We will see no end to this trouble until the man himself is gone.

These contrasting experiences should focus our thinking about the mission in Kosovo, as it becomes unavoidably plain that only U.S. Army and Marine ground forces can ensure a NATO victory.

In all wars, it is critical to distinguish between military and political goals. The Serb campaign of terror against the Kosovars began almost ten years ago, when Slobodan Milosevic took power in Serbia and adopted a policy of repression toward Kosovo. He eliminated the autonomy the province had enjoyed since 1974 and denied its ethnic-Albanian majority their basic civil rights. But the present rampage in Kosovo is only the most recent violence Milosevic has sponsored against neighbors that once were part of Yugoslavia. Since 1991, he has unleashed aggression against the Slovenians, the Croatians, and most lethally the Bosnians, at a cost of up to 200,000 lives.

The current U.S. and NATO action should be thought of as a long-delayed response to an extended series of deliberate and bloody provocations. Its proper military objective is to expel the Serbs who are committing outrages in Kosovo and permit the return of the Kosovars who have been forced to flee.

But the larger strategic purpose must be to remove the source of this ten-year terror. And that is Milosevic. If he stays in power, there will be more trouble. There are Serb populations in neighboring Montenegro, a republic of Yugoslavia, and in Macedonia, an independent country since 1991. Milosevic would be acting out of character if he allowed Montenegro to proceed unmolested toward democracy, as it has sought to do in recent years. Meanwhile, the Serbs' kidnapping of three American peacekeepers in Macedonia is a clear expression of Milosevic's territorial ambitions there -- the very ambitions that occasioned the peacekeeping presence in the first place. As for Bosnia, the Dayton accords will be in extreme peril if Russian arms are sent to resupply the Serbs.

The strategic purpose of sending troops to Kosovo is to stop Milosevic before he invades again; to remove a dictator who has been as successful at stirring up discord between Washington and Moscow since the Cold War ended as Marshall Tito was at working both sides of the street while it was in full swing. Republicans who are now slouching toward isolationism -- senators Trent Lott, Tim Hutchinson, Robert Smith, and others, whose party once stood for principle in foreign policy but now seems purely reactive to Clinton -- ask how many American lives Kosovo is worth. They are asking the wrong question. The right one is: How many more American lives will it be necessary to sacrifice if we fail in the Balkan war today? And how many American lives will be saved if we demonstrate to Saddam Hussein, the Iranian Mullahs, the maximum dictator of North Korea, and the Chinese leaders that the price for provoking the United States to war is very high?

Pushing the Serb security forces out of Kosovo would be a great humanitarian act. But actually returning stability to the Balkans would be an even greater strategic achievement, one that requires removing Milosevic from power. By doing this, the United States would make the world a safer place. By failing to do it, the United States would turn Serbia into a second Iraq: another U.S. mistake, setting the stage for some larger and more perilous conflict in the future.

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