PERSPECTIVE ON BOSNIA : A Balkan Vietnam Awaits ‘Peacekeepers’ : With U.S. experience as a guide--or Britain’s in Ulster--90,000 to 200,000 troops would be needed against terrorist forces.

The peace proposal developed under United Nations and European Community auspices would divide the former Yugoslav republic into 10 autonomous provinces, at least three of them under full Serbian control. Objections have been raised that this would reward Serbian ethnic cleansing. The alternative to a settlement that accepts the fact that some ethnic cleansing and territorial aggrandizement have occurred is one that permits all Bosnian refugees to return to their homes. Given the record of communitarian violence, this will happen only if outside forces intervene to keep the peace--to protect all groups, including Serbs, from terrorist acts by all others.

While there is no widely accepted methodology for estimating the military forces necessary to this mission, one may deduce from analogous historical cases that 200,000 troops could be required for at least 10 years.

The requirement for combat power for communitarian peacekeeping should be similar to the demands of counterinsurgency. These are driven by the size of the population and the territoryto be policed, as well as by the size and capability of the enemy. The problem of peacekeeping in Bosnia is thus similar to the security problem in Northern Ireland since 1969, and to the situation in Vietnam before the Viet Cong exposed themselves to destruction by superior U.S. firepower in the 1968 Tet offensive.

In both cases, committed, organized, violent groups with much popular support tried to attack their indigenous political enemies, who were assisted by the presence of outside forces--the British in the first case, Americans in the second. The strategic problem for these “peacekeepers” was to establish sufficient presence on the ground and in the population to deny the indigenous armed groups the freedom of action they needed to wage their “unconventional” warfare, and to maintain a degree of superiority that could defeat them whenever they tried.

Northern Ireland provides a good lower bound for the troops needed to police the ethnically mixed portions of Bosnia. The reason is simple: The British have faced very few actual combatants, the total in both the IRA (Irish Republican Army) and Protestant extremist groups ranging from a high of 1,500 in 1972 to perhaps 500 today. Yet the British Army and its allied local police and military forces have averaged roughly 30,000 since 1972. Bosnia-Herzegovina is about three times the size and population of Northern Ireland. Thus, even if only a small number of hardened fanatics were to resist a reversal of ethnic cleansing, 90,000 U.N. soldiers could be needed to police the settlement. And Northern Ireland has remained “hot” for 20 years.

The U.S. experience in South Vietnam could provide more realistic guidance for sizing U.N. forces if the 50,000 troops credited to the Bosnian Serbs oppose a restoration of an ethnically mixed Bosnia-Herzegovina. The Yugoslav army trained, organized and armed these troops to wage insurgent warfare. One would also expect resistance from Croats and Muslims unhappy with the precise terms of the settlement.

In 1968, the United States and South Vietnam pitted 1.2 million ground troops against 300,000 communist guerrillas and regulars. This 4-1 force ratio did not prevent the communists from killing nearly 15,000 Americans and tens of thousands of South Vietnamese troops that year. The United States controlled the air in South Vietnam, and heavily bombed both North and South Vietnam, yet did not prevent or even detect enemy preparations for the Tet offensive.

But the allies did stalemate the communists by the year’s end. Thus, 1968 suggests that at least 200,000 U.N. troops would be needed to control 50,000 armed Serbs. Since the Vietnam War was lost once U.S. troops left, the lesson is that U.N. troops would need to stay in Bosnia for a very long time.

If the United Nations and the European Community wish to reverse ethnic cleansing and compel Serbs, Muslims and Croats to live together in peace, 90,000 to 200,000 troops could be necessary.

To reduce opportunities for guerrilla violence, one should saturate the country with force, so the high end of the estimate is safest, but could still be too low. The majority would need to be the professional soldiers of the United States, Britain and France, because most U.N. members would be unwilling to risk many conscripts in Bosnia-Herzegovina. Two hundred thousand troops amount to roughly five divisions and their support units. The French and British have only enough force to send one division each; the United States would have to send three.

Professionals are not obliged to serve forever, and there would be few new enlistees for perpetual Balkan service. Personnel must be rotated once or twice a year; a conservative rule is two divisions at home to keep one deployed. Thus, most of the U.S. Army and Marine Corps (11 active divisions under Secretary of Defense Les Aspin’s proposed force structure), all of the British Army and all the professional elements of the (largely conscript) French Army could be required to support peacekeeping in Yugoslavia for many years.

The military competence and ferocity of the Balkan peoples suggest that the peacekeepers would suffer regular, perhaps heavy, casualties. Small wonder that Western commanders resist a deepening commitment.

While the acknowledgment of any Serbian gains is distasteful, the cost of re-creating prewar Bosnia-Herzegovina seems much greater than Western nations would be willing to bear.

The preliminary outline of the new peace plan appears sensible, but the devil is in the details. Negotiators should not attempt and observers should not demand political solutions that peoples and governments will not provide the military capabilities to police.