NEWS ANALYSIS : Europe’s Future to Reflect Watershed Summit’s Shifts : Diplomacy: Transformation stamps success on ever-warming U.S.-West German relationship.

LONDON — The sense of occasion surrounding the London NATO summit that ended here Friday left few in any doubt that the changes agreed to by the alliance’s 16 member countries represent a watershed development. But the London summit is likely to shape Europe’s future in ways that were hardly mentioned in the afterglow of Friday’s agreement.

“Europe has entered a new, promising era,” stated the opening sentence of the London Declaration, a document that sets out a new political role for the North Atlantic Treaty Organization and extends a hand of friendship to its old adversaries.

Above all, however, the declaration is a crowning success for an increasingly warm and close relationship between the United States and West Germany that has developed almost as quickly as German unity itself.

In the short term, the U.S.-German relationship is expected to smooth the diplomatic path toward Soviet acceptance of German unity.

Over the longer term, it is expected to shape internal NATO debate and relegate alliance hard-liners like British Prime Minister Margaret Thatcher to a minority voice of caution.

NATO’s new political role also raises the potential of the organization’s being eclipsed by the 12-nation European Community, whose own growing political dimension has become important glue in the process of Western European integration.

It is a relationship that is almost certain both to shape the future of NATO and to influence the tenor of overall transatlantic ties during the crucial decade ahead.

Indeed, it has already been a pivotal factor in the head-long rush toward German unification.

Only strong, unquestioning, American support silenced initial British and French reservations about German unity. Only unwavering U.S. backing has forced the Soviet Union to confront its inevitability.

“Without the American President, none of this would have come to pass,” Kohl told reporters Friday.

It was a phrase that has become a litany in the West German chancellery.

America’s size and distance from Europe helps ease public worries over German unity that gnaw at Germany’s immediate neighbors, making such strong support far more sellable in the United States than in Europe.

But the ties have also developed through good personal relationships between the Kohl and Bush.

“The chemistry works between us,” Kohl explained at a post-summit news conference Friday.

For the United States, the strength of these German-American ties has potential advantages that far outstrip those resulting from the revivified “special relationship” it enjoyed with Britain during the Reagan years.

At a time when a united Germany is about to replace the United States as Europe’s principal financier and grow in political stature, the German leadership feels closer to the United States than to anyone else.

“This will be the European decade,” Kohl said. “If the U.S. has a strong, healthy link in this direction, it can be of great use.”

Implicit in Kohl’s statement was the future economic and political dominance of a united Germany in an increasingly unified Europe.

But Friday’s declaration also carries unspoken risks for the United States and the NATO alliance in the coming years.

For the alliance’s new plan to emphasize its political rather than military dimension places it into what a number of analysts here see as an inevitable conflict of purpose with the 12-nation European Community. Many predict that only one organization can survive as a major player.

As the community moves toward full economic integration by the end of 1992, it has gradually developed the threads of a political cohesion that is likely to become the natural first place for its members to seek common positions.

Indeed, following a proposal by Kohl and French President Francois Mitterrand, the community later this year is scheduled formally to study the process of political union.

The danger, diplomats note, lies in the nearly total overlap of NATO membership within the community--Ireland is the only non-NATO nation--and the nearly total lack of common interests among the NATO members that are not in the community--the United States, Canada, Turkey and Norway.

“If you take the Soviet threat away, where are the shared interests between Turkey, Norway and Canada?” asked a seasoned European diplomat.

While Friday’s NATO declaration contains language approving the community’s move toward political union, concern was between the lines.

With key community figures, including External Affairs Commissioner Frans Andriessen, speaking of an eventual security dimension for the European group, the potential for competition can only grow, some observers believe.

But NATO has a trump card: It is the prime vehicle for keeping the United States involved in Europe and, at least for now, Europeans are united in support of continued U.S. presence.

Friday’s declaration also is likely to diminish the influence of advocates of a hard line on defense.

With Thatcher praising the London Declaration with an enthusiasm equal to both Kohl and Bush, the document signaled the end of an era in which tough rhetoric and unyielding positions set the tone.

Her warnings about the need for new and better equipment, and for nuclear modernization, and her recollections of how poorly equipped British soldiers were at Dunkirk carried the distinct ring of a last hurrah.

Her contributions were there, but as background music. Her considerable influence eroded by the new German-American relationship, she no longer determines the beat.

In the coming weeks, events may well be determined outside the alliance as the Soviet Union begins to assess the meaning of the London summit.

“I think the next move . . . is up to them,” Bush told a post-summit news conference.

WHAT NATO OFFERED MOSCOW

NATO leaders offered the Soviet Union and its allies a package of measures as proof that the Cold War is really over and that NATO, with a united Germany as a member, poses no threat. JOINT DECLARATION OF PEACE

NATO invited the Soviet Union and its Warsaw Pact allies to sign a joint peace declaration committing all signatories to nonaggression. Moscow has suggested a peace treaty. INVITATION TO GORBACHEV

NATO invited Soviet President Mikhail S. Gorbachev and leaders of other East European countries to address the North Atlantic Council, NATO’s top decision-making body. It is normally made up of foreign ministers but heads of government would probably attend to hear Gorbachev. ENVOY TO MOSCOW

NATO Secretary General Manfred Woerner will visit Moscow July 14 to brief Gorbachev on the summit results. President Bush said he expected to explain decisions to Gorbachev in person in a telephone call sometime in the next two weeks. NUCLEAR STRATEGY

NATO will soften its strategy to make nuclear arms “weapons of last resort,” moving away from the so-called doctrine of “flexible response,” developed to counter any massive Soviet conventional attack.

NATO offered to withdraw all U.S. nuclear artillery shells from Europe if the Soviet Union does the same. CONVENTIONAL FORCES

NATO wants to intensify negotiations for an agreement to cut conventional forces in Europe (CFE). When that treaty is signed, NATO will give a commitment on troop levels in a united Germany. Moscow, which opposes united German membership in NATO, has been pressing for limits on the size of a united Germany’s armed forces. NATO says once a CFE treaty is signed, follow-up talks on a new agreement should begin to negotiate further cuts.

NATO will move away from a strategy of “forward defense” and will move to smaller, more mobile multinational units that can be reinforced if needed. CSCE’S STRONGER ROLE

NATO proposed new institutions for the Conference on Security and Cooperation in Europe, including a secretariat, a body to monitor elections, a center for the prevention of conflict, and a parliamentary Assembly of Europe.