WASHINGTON -- U.S. military planners involved with the Bosnia situation don't know if they are about to unleash Desert Storm II or reprise Somalia's Operation Restore Hope, and this is making their job enormously complicated.
Right now, the biggest focus is on shaping a ground-oriented force of up to 75,000 U.S. and allied troops that could keeping warring factions apart if a peace plan takes effect.
But U.S. and European military leaders also are deeply involved in planning joint air strikes against the Serbs in case they continue efforts to "cleanse" Bosnian Muslims.
The two types of operations -- attacking the Serbs or enforcing a shaky peace pact -- would require vastly different kinds of troops, weapons and strategies. The politics of dividing roles among multinational forces is difficult, and so is the timing.
The Pentagon has just begun looking into new approaches for regional wars that might not merit the awesome firepower used against Iraq -- or that might not be winnable as quickly.
Western leaders, working through the North Atlantic Treaty Organization, have drafted preliminary plans for peacekeeping that call for tens of thousands of U.S. and allied ground assault troops to quickly occupy key seaports and airstrips under allied air cover.
In one scenario, 2,200 U.S. Marines from Camp Lejeune, N.C., would storm ashore to secure two ports on the Adriatic Sea near Bosnia. The Marines now are waiting aboard ships off Spain, two days away.
As the Marines land, several thousand Army paratroopers would take control of the airfield at Sarajevo and other sites. They could come from Army units in Italy or Germany or from the 82nd Airborne Division at Fort Bragg, N.C.
Following close behind would be 12,000 combat soldiers, plus tanks and other armored vehicles, from the 1st Armored Division, based in Bad Kreuznach, Germany.
All told, planners now envision using 20,000 to 25,000 U.S. troops in an initial force of perhaps 50,000 allied soldiers. Pentagon officials said the U.S. presence could grow to as many as 34,000 soldiers at one time, with large contingents rotated in and out if the peacekeeping operation dragged on for months or years.
Over time, the planners envision that troops from a number of other Western nations -- and possibly even Russia and India -- could swell the total force to 75,000.
But critics question whether other countries will come through with that many soldiers. They recall that the United States operated under the United Nations flag during the Korean War, but supplied 90 percent of the soldiers.
Some also warn that a peacekeeping operation could deteriorate into a broader war, enmeshing Western troops.
"If the United Nations decides on a peacekeeping force, I think we ought to be fairly represented in it," said retired Rear Adm. Eugene Carroll, deputy director of the Center for Defense Information, a private analytic group.
"But once we get in there, there will be breakdowns," he said. "There will be snipers, and there will be booby traps and land mines, and things could evolve into a pure shooting war" involving allied troops.
Others say the Bosnian Serb army, which has 35,000 troops of the former regular Yugoslavia army and 35,000 less trained irregulars, makes a much more dangerous opponent than the warlords and youth gangs operating in Somalia when U.S. forces landed in December.