The logic of the painted helmet: More countries must join the UN force in the Balkans, says Lawrence Freedman

Once again the former Yugoslavia has forced Western leaders to confront the harsh realities of power and responsibility. The Owen-Vance peace plan will now be reinforced by the active involvement of the United States and, probably, Russia. The local players accept that they are in the endgame of the negotiating process and that, if there is to be a settlement, it will be backed by peace-keeping forces representing the major powers. They know that plans are afoot for the introduction of up to 40,000 outside troops into Bosnia to ensure that any agreement is upheld.

The events of the last few days have illustrated some basic truths. Assertions of collective outrage without credible means of coercion can do little in the face of deep intransigence and bitter violence. Outsiders cannot hope to influence the course of such conflicts unless they can also influence the struggle for land which lies at their heart, and this means the introduction of troops on the ground. Moreover, if ground troops are to be available in the numbers needed to make a difference, the US must play its part. And if the US is to be involved in a multinational operation in Europe, this can be organised only through Nato.

The Clinton administration has accepted this logic, to its credit, despite evident misgivings - especially in the military. Entanglement in messy civil wars of indefinite duration is exactly the sort of intervention the American military has been desperate to avoid. Generals spoke disparagingly of troops in 'painted helmets' engaged in 'constabulary duties', as if this was not a proper role for US soldiers. Now they have found that so long as the US pursues an activist foreign policy, military policy must fall in line.

The same logic is equally disturbing for the French. It conflicts in many ways with their vision of a European defence entity in which Continental powers would take responsibility for Continental problems. But they have seen Germany's impotence when it comes to involvement in military operations with any risk of combat, and have been steadily strengthening their position in the formal Nato machinery.

In a different way, Bosnia also presents a challenge for the United Nations. The UN must accept that an operation of this size and complexity must subcontract basic functions to Nato. The current headquarters of the UN humanitarian mission in Bosnia is, in fact, a transplanted Nato command centre (minus the Germans). Local conditions do not allow for the improvised, shoe-string peace-keeping operations put together by the harassed and under- resourced UN Secretariat. An efficient command and control system and supply chain need to be in place within weeks if not days of a settlement being agreed.

Nato may provide the only possible framework for a ground operation, yet there are profound limits to the role it can play. However high it might score, compared to the other candidates, when it comes to proficient organisation of a multinational force, it comes in low on political legitimacy. Nato is not seen by the Serbs as an impartial, neutral force.

If the multinational force is to be seen to reflect the will of the international community, not just one group, then its membership must be widened and its authority clearly derived from the UN Security Council. This is why all those involved are determined to bring non-Nato contingents into the force, especially the Russians, who have consistently been more sympathetic to Serbian concerns.

The UN link is reinforced if the troops are part of a traditional blue-helmeted operation for peace-keeping rather than peace-enforcing (as in the Gulf). A peace- keeping force does not expect combat. It will monitor adherence to an agreement and reflect international expectations of compliance. But if it is to work, the parties concerned must consent to its presence: if consent is withdrawn it cannot continue.

The new force would build on the much smaller operation already in Bosnia which is designed, in the absence of a peace to keep, to bring humanitarian relief. This has the same rules of engagement, but must inevitably negotiate the consent of the parties on the ground at each stage.

The cost of the current Bosnian force is borne by the participants. This was the only way Boutros Boutros-Ghali, the UN Secretary-General, would agree to its dispatch. This, it is now accepted, was a bad idea. It creates resentment among those being asked both to risk the lives of their troops and to pay for the privilege, undermines the concept of collective international responsibility, and makes for real practical problems in getting funds through. Any new force will be financed with a charge on all UN members - although they may dislike sustaining a potentially lengthy operation organised on Nato's comparatively lavish scale.

Political control of this force will be exercised through the UN. For the Americans, used to considerable freedom of manoeuvre, this will be a novelty. While they may expect to take command of the forces on the ground, the commander will need to learn to take his political guidance from New York, not from Washington.

This would be a source of strain at the best of times, but doubly so in such unpropitious circumstances. No operation in the former Yugoslavia can take the old- fashioned form in which the peace-keepers interpose themselves along a ceasefire line. If agreement is reached along the lines of the Owen-Vance plan, Bosnia will be a patchwork of ceasefire lines. In speeches at the UN the rights and wrongs of the conflict may seem crystal clear: on the ground, inexcusable conduct on the part of the assumed victims may start to blur the moral guidelines.

Next door, in Croatia, an apparently successful operation has already started to come apart because the political understandings on which it was based were so fragile. When its current mandate expires this week, the operation will at best be continued for only a few more weeks. Local opposition to any deals in Bosnia could make life uncomfortable for the peace-keepers and confront them with the familiar dilemma of having to stick to their restrictive rules of engagement while things deteriorate, or take a more active role at the risk of losing their impartiality and raising the military stakes.

The process of introducing the force could be the most difficult of all. Final demarcation lines agreed in Geneva might lead to new bursts of ethnic cleansing, as indeed is already happening. This underlines the most basic lesson of all. The potential for chaos is immense in relations between the negotiating team, national capitals, the Security Council, the UN Secretariat, Nato, the field commanders and then the local political leaders and their commanders. However well-disciplined and dedicated the peace-keepers, they cannot succeed if their political guidance is confused.

(Photograph omitted)