DRIVEN by developments at home, Washington is edging into a full-fledged debate over the role the United States should play abroad.
It has the faint echoes of a debate that occurred in the late 1930s over whether the US should get mixed up in the political affairs of Europe, then on the brink of war. That debate pitted ''isolationists'' against ''internationalists.''
Today, the issue is not whether but how the US should engage in a world where, all sides agree, it has an inevitable role to play. The partisans in this debate are ''multilateralists,'' led by the Clinton administration, and ''unilateralists,'' led by the new Republican Congress.
''There's no question that there's a fight for the soul of foreign policy between Congress and the Clinton administration over the questions of engagement abroad,'' says a congressional source.
The US engaged in its first significant debate over its role in the world after World War I when President Woodrow Wilson unsuccessfully campaigned to get the US to join the League of Nations. After World War II, a major international threat -- Soviet expansionism -- focused national attention on foreign policy issues.
Today, absent either a major threat or a president aggressively pressing a foreign-policy agenda, the issue of the US role in the post-cold-war world has been consigned to the periphery of the national political debate.
But three recent events have brought it to the fore:
*The just-concluded, partially failed United Nations peacekeeping mission in Somalia, which has made Americans gun-shy about future entanglements abroad.
*The recent passage by House Republicans of controversial legislation that would severely restrict future UN peacekeeping has concentrated the minds of policy makers and analysts in Washington.
*The incipient presidential campaign has forced Clinton and potential Republican challengers to define and defend their basic foreign-policy principles.
In fact, most agree on the main goals of US foreign policy: The US needs to preserve access to Middle East oil, prevent foreign powers from establishing a hostile presence in the Western Hemisphere, and help maintain stability in Western Europe and East Asia.
The debate over foreign policy has partly to do with specifics, like how much support to give Russian President Boris Yeltsin, whether to cut foreign aid, how far and how fast to expand NATO, when and where to intervene militarily abroad.
BUT the real debate, aired most recently in the current issue of the journal ''Foreign Policy'' and at a conference convened by the Nixon Center for Peace and Justice in Washington, is over the crucial issue of means.
As former Secretary of State Henry Kissinger put it at the Nixon conference: The question is whether the US can ''act internationally only as a result of multilateral consensus. That is in my view what the debate is all about at this moment.''
On one side of the debate are President Clinton and his secretary of state, Warren Christopher, who accuse Republicans of isolationism. They say the US should advance its interests by acting alone, when necessary, but in concert with other nations, when possible, through international organizations like the United Nations and NATO.
American leadership requires ''that we galvanize the support of allies, friends, and international institutions in achieving common objectives,'' Mr. Christopher writes in the spring issue of ''Foreign Policy.'' Going it alone, he says, is ''naive'' and forces the US to decide between acting alone or doing nothing when humanitarian and political crises arise.
Leading voices on the other side include Senate majority leader Bob Dole (R) of Kansas, a Republican presidential aspirant, who warns that the Clinton administration has nourished a resurgence of isolationism with ''irresponsible'' internationalism in places like Somalia, where US troops were part of a UN peacekeeping force.
''Subcontracting American foreign policy and subordinating American sovereignty encourage and strengthen isolationist forces at home -- and embolden our adversaries abroad,'' Sen. Dole writes in point-counterpoint with Christopher in ''Foreign Policy.''
''In the end, America cannot derive its motivation from an international consensus,'' Mr. Kissinger concurred at the Nixon conference. ''It has to develop its specific purposes and then try to shape an international consensus.''
Another group of foreign policy experts, mostly outside the government, says the goal of the US should be to amass enough economic, political, military, and technological power to ensure its security and prosperity in the midst of global turmoil.
''US policy should focus on equipping America to flourish in this world, not on transforming or even stabilizing it,'' says Alan Tonelson, of the Economic Strategy Institute in Washington.
Just how far the US should go it alone is a matter that has divided the Republicans themselves, as illustrated by the question of whether the US should ignore a UN consensus and exempt Bosnia from a 1992 arms embargo on the former Yugoslavia.
Dole is leading the charge to do so. Clinton, with the reluctant concurrence of some Republican ''internationalists'' like Kissinger, argues that unilateral action by the US in Bosnia could make it easier for France and Russia to unilaterally break a UN embargo on Iraq that the US supports.
''Ironically, Dole is the guy who wants to act unilaterally and the unintended result will be a wider war and more pressure for the US to become involved militarily in a marginal area,'' Mr. Tonelson says. ''Clinton wants to keep the embargo to preclude that very possibility.''
Unilateralists tend to define US interests more narrowly than multilateralists, diplomatic analysts say. Their litmus test for US involvement abroad is likely to be whether a crisis directly affects US security or prosperity, not whether it affects the stability or prosperity of another country or of the entire international system.
But the effect of this difference is likely to be muted in practice. Chastened by Somalia, neither Clinton nor any successor is likely to venture into engagements abroad where US security interests are not reasonably compelling. Nor are they likely to blur the distinction, highlighted by Somalia, between peacekeeping, which UN forces are good at, and peacemaking, which they are not.