THE centerpiece of this week's NATO summit was an arms-control initiative that looks like something the Soviets might have dreamed up. That's no accident.
In calling for deep reductions in United States troops and Western aircraft in Europe, President George Bush has sought to grab the initiative in East-West dealings from Soviet leader Mikhail Gorbachev. He also gambled - successfully - that the moves would help smooth a dispute within NATO over short-range nuclear weapons.
Mr. Bush came to Brussels under pressure to reassert Washington's leadership in the Western alliance. And he appears to have succeeded.
``Finally, the Americans are exerting their historic role in the alliance,'' says one West European diplomat, clearly relieved by the successful outcome of the meeting.
The President's arms initiative, which was formally endorsed by the allies on Tuesday, poses a firm challenge to the Soviets. The US would pull some 30,000 combat troops out of Europe, but only if the Soviets agreed to much deeper cuts in its Europe-based troops. Planes would get drawn down to equal levels - at 15 percent below NATO's current numbers. All withdrawn troops would have to be demobilized and the airplanes destroyed.
But the timing and nature of the new proposals could cause problems for both sides. The ideas are supposed to be introduced in September at the on-going conventional arms talks in Vienna. Bush said a full agreement - covering tanks, artillery, armored troop carriers, airplanes, and troops - could be hammered out within six months or a year. The plan could be fully implemented as early as 1992, he said.
In the past, NATO argued that reductions in planes and troops are too hard to verify and should be put off until a future round in the Vienna negotiations.
President Bush, speaking to reporters after the summit, insisted his plan is feasible.
But British Prime Minister Margaret Thatcher expressed mild skepticism. ``I think [six months] is quite optimistic,'' she said, then added pointedly, ``very optimistic, extremely optimistic.''
The French, meanwhile, have emphasized that no dual-capable aircraft - those able to carry nuclear or conventional bombs - should be included in the dealings. France doesn't take part in NATO's integrated defenses and is worried that the talks could impinge on their nuclear forces, which include nuclear-capable airplanes.
Soviet Foreign Minister Eduard Shevardnadze said Tuesday that Bush's disarmament plan was a serious step in the right direction. But he was cautious about Bush's deadline for hammering out an agreement on cuts in conventional arms and troop levels. ``As I said, the proposals have to be studied carefully. The question is how this can be done practically,'' he said.
The Soviets have insisted all along that troops and airplanes should be part of the Vienna talks. In addition, they've already pledged to make one-sided reductions that go far toward achieving the troop level envisioned in the NATO proposal.
But the Soviets may have trouble with the West's ideas on planes, since NATO doesn't recognize the East's distinction between ``defensive'' and ``offensive'' aircraft.
They could also face a time crunch. Soviet officials, speaking recently about their unilateral withdrawals of tanks and troops already under way in Eastern Europe, complained that they had trouble moving so much equipment through the heavily burdened rail networks.
Timing of the conventional reductions was crucial, however, in working out a compromise between Bonn and Washington over short-range nuclear arms. By speeding up the timetable in Vienna, the US sought to ease West German fears that short-range negotiations would get pushed off until late in the 1990s.
The West Germans came to Brussels insisting that short-range arms should be thrown on the negotiating table with the Soviets as soon as possible, while the US sought to put off negotiations until after significant progress is made in cutting conventional arms.
Under the deal worked out here, the US agreed to open talks with the Soviets aimed at reducing - but not eliminating - short-range weapons. But the new talks can't begin until after an accord is reached in Vienna on cutting tanks and troops. Even then, the implementation of the nuclear accord would have to wait until after reductions in conventional weapons were complete.
``This is something we can live with,'' says a spokesman for the West German Foreign Ministry.
West German Foreign Minister Hans-Dietrich Genscher has fought the hardest for early negotiations. But in the end, he was isolated among the NATO partners - who were eager to avoid letting the 40th anniversary summit of the alliance end under a cloud of lingering disagreement.
Indeed, both Bonn and Washington made concessions. The West Germans agreed to rule out the complete elimination of short-range arms - the so-called ``third-zero'' option - in return for a pledge from Washington that the talks could begin before all the conventional reductions are made.
Still, the agreement only puts off some tough problems - it doesn't solve them.
West German officials, for instance, privately insist that the agreement doesn't completely rule out a ``third zero,'' since it only says it's out of the question for the foreseeable future.
The West has also pushed off a tough decision about the modernization of the short-range Lance missile. Bonn has argued that the decision to update the weapons shouldn't be taken anytime soon, since that might provoke ill-feelings in the East at a time of wide-reaching political changes.
In a major summit document - known as the comprehensive concept - NATO reaffirmed that the Lance should be kept up-to-date, but avoided making a decision about updating it until 1992. By then, say the West Germans, the issue may look entire different - since the East-West talks on reducing their numbers may already be under way.
The comprehensive concept is a broad framework for East-West arms issues which attempts to map out what weapons the West will need in the future. The document, for instance, calls for the elimination of chemical weapons and reaffirms the West's long-term reliance on a mix of conventional and nuclear arms.
Meanwhile, NATO must now prove that its freshly polished harmony can hold up under the steady pressure of new initiatives from Moscow.
Indeed, even as the summit was ending on Tuesday, word came from the Soviet capital that Mikhail Gorbachev was announcing deep cuts in his nation's defense expenditures. President Bush said he welcomed the news, but emphasized that the West would fight to retain the upper-hand in East-West dealings.