Lebanon's European peacekeepers uneasy about US show of force

British Prime Minister Margaret Thatcher urges caution. France's Foreign Minister Claude Cheysson expresses ''unease.'' And Italian Foreign Minister Giulio Andreotti fears ''an uncontrollable fire.''

In these terms, the three European members of the Beirut peacekeeping force have warned the United States not to undertake any dramatic retaliation for the bomb attack that killed 230 marines.

Officials contacted in London, Paris, and Rome say they know of no specific retaliation plan. On the big question of Lebanese strategy, they add that they remain in accord with Washington. Despite the recent attacks, their troops will remain alongside the Americans in Beirut in order to keep Lebanon from breaking apart and igniting another Middle East war.

But in the wake of the Grenada invasion, the massing of American forces off the Lebanese coast has raised to the surface differences of approach that threaten to undermine cooperation. Yasser Arafat's eclipse has sharpened these differences.

The Europeans have always said they would not stretch the self-defense part of the multinational force's mandate to permit reprisal raids outside Beirut. Now they fear the Americans, in increasingly close coordination with the Israelis, are going to create even more problems by pushing too hard.

A large-scale US riposte ''would light a fire in the region,'' Mr. Andreotti warned this week. He added, ''This fire would spread indiscriminately.''

Mr. Cheysson expressed similar sentiments in comments to the National Assembly.

And although Margaret Thatcher kept her reported fears private, she did tell Parliament that ''nothing should be done which jeopardizes or hinders the (Lebanese) reconciliation talks.''

American and European points of view diverge over these reconciliation talks in Geneva, currently recessed. American diplomats say they are important but stress they have other cards to play in the region. Thus, the show of military force and perhaps later the launching of a new diplomatic roving mission.

The Europeans, meanwhile, see the talks as a make-or-break effort. They argue that other American efforts, particularly the military ones, only increase tension in the region by bringing the superpower rivalry into play.

The European nightmare is a Lebanon divided between Israel in the American camp and Syria in the Soviet camp.

''The partition of Lebanon,'' French Prime Minister Pierre Mauroy warned recently in a major policy speach, ''is the road to a regional Yalta, the partition of the region into zones of influence dominated by the great powers.''

According to the Europeans, the United States wrongly blames the Soviets for inspiring all the trouble in the Mideast. For example, the Europeans doubt the Soviets had any role, even an indirect one, in the Beirut bombings. And they minimize Soviet influence over Syria.

''We don't think Syria can be grossly cataloged as a satellite of the Soviet Union,'' Mr. Andreotti stressed this week.

As a result, the Europeans believe Damascus can be wooed diplomatically. They criticize the Reagan administration's reluctance to deal with the regime of President Hafez Assad during the original Lebanese-Israeli negotiations last spring.

''The Americans didn't pay enough attention to Syria,'' a French Foreign Ministry official explained. ''The Syrians play an essential role. They cannot be excluded because Washington fears they are too close to Moscow.''

The final European criticism is that the US has failed to take proper note of the Palestinian problem. Europeans say the US lack of concern for the intra-PLO fighting in Tripoli has accentuated Europe's fear that Washington would be delighted to see the Palestine Liberation Organization knocked out of the Mideast equation. Europeans believe such a development would increase tension in the area.

So they have been frantically trying to save Arafat's neck. Italy's Andreotti flew to Damascus to plead with Syrian leaders to spare him. France's Cheysson called the fighting a ''tragedy,'' and rumors are circulating that the French will evacuate Arafat to their aircraft carrier off the Tripoli coast.

Despite all these differences, none have so far caused any serious problems between Washington and its allies.

For one thing, the Europeans realize they don't have the power to impose any answers. For another, the Europeans continue to insist that the general agreement with Washington on Lebanese strategy is more important.

Less than two weeks ago, after all, the American, British, French, and Italian foreign ministers met here and reached agreement that the peacekeeping force would remain at its present size of just under 6,000 men.

The ministers also agreed that the troops would stay only in Beirut and would not intervene in the Lebanese factional fighting except in self-defense.

Only a unilateral American escalation could destroy this unity.

''We hope the Americans are just playing psychological warfare,'' a French Foreign Ministry official said. ''But if they aren't, and there is a large riposte, there will be problems.''