THE United States would be better served if Congress and the President would stop blaming each other for the failure of our Lebanon policy and try to learn from the experience. A good place to start would be with the collapse of the multinational force. Vietnam demonstrated the hazards of military intervention in internal conflicts; Lebanon demonstrates the dangers of attempting to co-opt the peacekeeping role of the UN.
Eighteen months ago, following the massacres in the Sabra and Shatila refugee camps, the UN Secretariat was ready to send a peacekeeping force to Beirut. A Security Council resolution, with US and Soviet support, had been passed asking the Secretary-General to begin plans for the deployment of UN forces. But the new Lebanese President, Amin Gemayel, wavered and finally decided that his political fortunes would be better served by returning the US-led multinational force. When President Reagan agreed to Gemayel's request for its return, US prestige was once again committed to the fortunes of a weak ally embroiled in an internal struggle. Once in Beirut, the US forces were drawn into the escalating violence that led to the collapse of the peacekeeping mission.
Peacekeeping forces have been developed by the UN to help restore order in conflicts in which the superpowers are not directly involved, to insulate those conflicts from superpower intervention, and to provide an opportunity for tensions to subside. Their tools are mediation, persuasion, and patience. Such tools work only when the mediator is not suspected of selfish motives, only when his interests are seen as directed solely toward peace and order, as opposed to the preponderance of one faction.
Beginning with the UN Emergency Force sent into the Sinai after the Suez War of 1956, three principles have guided the dispatch of peacekeeping forces: consent, neutrality, and peacekeeping as opposed to peace-enforcing activities. The forces must be sent with the consent of the host government; they must be composed of ''nationals of countries other than those having permanent membership on the Security Council'' and neutral to the conflict at hand; and they must have no military objectives.
The multinational force entered Beirut with the consent of the fledgling Gemayel government, but it was never seen as a neutral presence. The identification of the US forces with Gemayel and their assistance in building his new Army left his political opponents with no option but to seek support from the Syrians and, indirectly, the Soviets. Intervention by one superpower opened the door to the other. When the New Jersey fired its 16-inch guns in support of Gemayel's troops the battle was joined, and the peacekeeping mission was fatally wounded.
It did not have to happen. President Reagan could have refused Gemayel's request for the return of the multinational force and insisted upon a UN peacekeeping mission in its place. That is what Eisenhower did when the Soviets proposed a joint US-Soviet military force in Suez in 1956 and when members of the Congolese government asked for US intervention in 1960. That is what Nixon and Kissinger did when the Soviets demanded a joint US-Soviet peacekeeping force to enforce the cease-fire in the Yom Kippur War of 1973.
If Reagan had followed those precedents, Gemayel's only option would have been to accept a neutral UN peacekeeping force. Gemayel's political opponents would not have been forced to ally with the Syrians to counter the power the Phalangists gained from the US commitment. Unlike the Marines, the UN force would not have been considered a legitimate target for terrorist raids. It might have worked. If it did not and the fighting resumed, the UN forces would have been forced to stand aside, as they have when peacekeeping efforts have collapsed in the past. But US costs in lives, prestige, and influence in the Middle East would have been far lower.
Now that the US has met Soviet demands for a complete withdrawal from Lebanese waters, it may again be possible to pass a Security Council resolution to send in a UN peacekeeping force to monitor the next cease-fire in Lebanon. If we want to help bring peace to that troubled country we should not let the opportunity pass.
Russell J. Leng is professor of political science at Middlebury College.