NEWS ANALYSIS : President Sends Mixed Signals to U.S., Serbs : Conflict: Clinton talks tough to rebels even as he reassures Americans on limited involvement.

Standing on the verge of wider military involvement in the Bosnian war, President Clinton broadcast two deeply conflicting messages Friday: to the Serbs--NATO means business; to the American people--no ground troops.

Clinton’s statements, repeated several times in a news conference, underscore the conflict at the center of U.S. policy toward Bosnia-Herzegovina. Clinton is willing to use force to try to bring the Serbs back to the negotiating table, but only to a point. The Administration’s policy is defined not so much by its objectives as by its limits.

The President and his aides were cheered by reports that Bosnian Serb forces had agreed to a cease-fire around the Muslim enclave of Gorazde in response to NATO’s demand for a demilitarized zone there. But U.S. officials have made this much clear: If the Serbs defy the United Nations and the North Atlantic Treaty Organization, as they have frequently in recent weeks, and if the cost of punishing them becomes too high, Clinton would be willing to halt the operation and accept a failure rather than be drawn more deeply into the conflict.

While the President has refused to say so explicitly, he telegraphed his position by repeatedly ruling out the introduction of U.S. troops into the conflict.

“If what we are doing doesn’t work, then I will consider other options,” Clinton said. And he repeated that “the Bosnian Serbs should not doubt NATO’s willingness to act.”

Clinton reiterated this week that those options include the possibility of lifting the international arms embargo that has blocked weapons shipments to the Bosnian government.

But, Clinton added, “there has categorically been no discussion in which I have been involved, or which I have encouraged or approved, involving the introduction of American ground forces into Bosnia” except as peacekeepers after a peace treaty has been signed.

Administration officials concede the consequence of such a policy: Clinton cannot reassure Americans without comforting the Serbs as well. It is possible, they admit, that the limits of the U.S. position could encourage the Serbs to defy NATO’s newly stated resolve, hoping simply to outlast U.S. patience.

That is the risk of the U.S. strategy. The hope, by contrast, is that the Serbian leadership will decide, as U.S. experts have long predicted, that their forces already have all the territory they want and will not be willing to endure much more pain for only marginal gains.

Speaking after a meeting with Greek Prime Minister Andreas Papandreou, whose country has relatively close relations with Serb-led Yugoslavia, Clinton appealed to Serbian leaders to make exactly that decision, saying they “need to assert themselves at this moment” to control more aggressive military leaders and “avoid further wreckage.”

Administration officials say that so far, they have been unable to say for sure precisely who is in control of the Bosnian Serb forces--whether the civilian leadership can really negotiate an agreement that the military will abide by. In addition, they are uncertain about how much control can be exerted by the leadership of the neighboring Yugoslavia, which has armed and supplied the Bosnian Serbs.

Clinton also sought, once again, to reassure the Serbs that NATO’s actions are not designed to “win a military victory on the ground” for the Bosnian government or to make “a measurable and dramatic change of the situation on the ground.”

The reason for the strictly limited U.S. mission is clear. U.S. officials worry about the consequences of failure in Bosnia, both for the Bosnians and for broader U.S. credibility around the world. They admit that a U.S. failure in Bosnia could embolden other U.S. adversaries, most notably in North Korea.

But against that potential, Clinton and his aides balance a stronger fear--a repeat of Vietnam. Several Administration officials, most notably National Security Adviser Anthony Lake, were involved in various stages of the Vietnam debacle. With that experience in their minds, Clinton and his advisers have been determined not to allow themselves to be drawn further into Bosnia’s warfare by the seductive logic of escalating intervention.

Asked about the U.S. “exit strategy” in the current conflict, Clinton made a clear, although unstated, reference to the ghost of Vietnam.

“It is difficult to analogize this conflict from the point of view of the United States and the United Nations to others which occurred during the Cold War and which had some sort of Cold War rationale, some of which sometimes broke down,” he said. “It’s important not to be too arrogant about our ability to totally dictate events so far from our shores.”

Clinton’s advocacy of limited force in Bosnia received a boost from his visitor. The war in Bosnia is “a fire that can spread very fast,” Papandreou said in a statement opening the news conference. It is “a tragedy indeed, a great tragedy.”

But, he warned, the danger of NATO’s policy is that “step by step we may be dragged into a land war which would be really, by modern standards, a tragedy much greater than we have seen in Bosnia.”

Papandreou’s presence on the podium was something of a personal triumph for the Greek leader, who was effectively barred from the country during his previous eight-year stint as prime minister by the refusal of former Presidents Ronald Reagan and George Bush to meet with him in Washington. The previous Administrations believed that his policies were anti-American.

Clinton Administration officials argue that Papandreou has mellowed this time around and, in any case, find his former positions less troubling than the Republican Administrations did.