Bonn — Nearing the finale of his carefully composed European mission, President Reagan made another major peace gesture - on conventional force reductions in Europe.
Significantly, he chose West Germany as the site for the proposal, the critical borderland where the NATO alliance faces the Warsaw Pact's might.
Reagan proposed, in an address June 9 before the Bundestag (National Assembly), that the two competing alliances each reduce their ground and air force troop levels to 900,000. By United States estimates, this would mean a cut of 91,000 NATO personnel, and 262,000 from the Warsaw Pact forces. By East-bloc estimates, the Warsaw Pact would have to draw down or cut some 112,000 personnel.
The President's offer completes the Reagan arms control plan, adding the third and final stage, conventional force reductions in Europe, to his previous arms reduction initiatives.
On Nov. 18, 1981, Reagan called for reducing to zero any land-based intermediate-range nuclear missiles in Europe. Then on May 9, 1982, he asked the Soviet Union to engage in a new round of strategic arms reduction talks in late June (since set for June 29). The strategic arms reduction talks, or START, would reduce the numbers of ballistic missile warheads and missiles, and set a ceiling on other strategic weapons including ballistic missile throw weight at less than current American levels.
''The muscle of Soviet forces in Central Europe far exceeds legitimate defense needs,'' Reagan told the Bundestag on the eve of a NATO summit meeting here in Bonn. ''Their presence is made more threatening still by a military doctrine that emphasizes mobility and surprise attack. And as history shows, these troops have built a legacy of intimidation and repression.''
To the West Germans, the Reagan conventional force cut offer was welcome for reasons that go beyond the reduction of troops by 100,000 or 200,000 personnel. It offered a belated gesture of support for Chancellor Helmut Schmidt and the moderates in West Germany whose support has eroded, at least partly, because of past Reagan statements or actions on military and economic matters.
Schmidt was an architect of the December 1979 two-track NATO strategy - to deploy intermediate range missiles in Western Europe while seeking mutual balanced force reductions in the ongoing Vienna talks. Reagan campaign statements that struck West Germans as warmongering, careless administration talk of ''limited'' nuclear war, or of nuclear warning shots that would certainly be fired over West German heads, provoked unrest in Europe.
If Schmidt sought reelection now, he would lose, concede leaders of the chancellor's party, the Social Democrats. The opposition Christian Democrats, who outpolled the Social Democrats in last weekend's Hamburg state elections, are expected to win again in the Hesse state balloting in September.
Schmidt's coalition could unravel shortly, well before the 1984 West German elections. Reagan, belatedly the Germans think, has strengthened moderate elements in West Germany by emphasizing negotiations with the Soviets on arms.
Reagan came down clearly on the side of the ''Atlanticists'' - those elements in America and Europe who emphasize US links with Western Europe - at the expense of the ''unilateralists'' who favor a go-it-alone approach.
''Some Americans think that Europeans are too little concerned for their own security. Some would unilaterally reduce the number of American troops deployed in Europe,'' Reagan said. ''And in Europe itself we hear the idea that the American presence, rather than contributing to peace, either has no deterrent value or actually increases the risk that our allies may be attacked.''
Europeans have been worried that Mr. Reagan and some in Congress might become too preoccupied with Western hemispheric matters, or with Pacific nation links.
''We also are resolved to maintain the presence of well-equipped and trained forces in Europe,'' Reagan said, ''and our strategic forces will be modernized and remain committed to the alliance.
''We are with you Germany. You are not alone.''
To heighten the sense of US-German fraternity, Reagan also announced that West German President Karl Carstens would visit the US in October 1983 to celebrate the 300th anniversary of German colonization of America.
''A solidarity emphasis was needed in the Western alliance after all the statements of the last year,'' said a West German official.
''The peace movements in America and Europe have two roots in common,'' says Ulrich Steger, member of parliament from the Ruhr region, ''there is a fear that the world has become more dangerous the last few years. The second factor has been the rhetoric of the Reagan administration.''
Reagan did not deal with West Germany's economic differences with the US, which were not wholly resolved at the summit. ''Unemployment is the highest in 20 years in Germany,'' said Steger, an economic spokesman for his government. ''This is a waste of economic resources.
''Politically, the most difficult task is to adjust Germans to declining expectations,'' says Steger.