West German Chancellor Helmut Schmidt said yesterday that President Carter's effort to reduce U.S. oil imports was not only important for U.S. economic health but was crucial to maintaining what he called the "economic fabric of the world at large."

Schmidt's comments, made during a lengthy and wide-ranging interview in his office, are the closest he would come to saying publicly what is, in fact, a worsening nightmare for many European leaders.

The fear is that the continuing pile up of huge American trade deficits since 1976 - now running at an annual rate of $30 billion and caused mostly by heavy crude oil imports - is threatening not only to wreck the world's economic equilibrium by weakening the dollar but is also concentrating enormous dollar wealth in a handful of Persian Gulf and Middle Eastern countries, especially Saudi Arabia.

In this view, these countries although seemingly stable now, are vulnerable to political overthrow, assassination or revolution. They could also cause unintentional damage to economic stability by the sheer volume of their investments in the West, or shifts in such investments, at a time when there seems to be a premium on short-term gains in many places.

Although Schmidt continues to have serious differences with the Carter administration on economic policy - particularly with the defense of the dollar's value overseas - he said yesterday that he welcomed the president's dual efforts to fight inflation and crub oil imports and wished him success.

The grey-haired, 59-year old chancellor is the dominant figure in Western European politics and West Germany is the most important economic and military ally of the United States in NATO. In the first 15 months of the Carter administration however, Bonn has found itself embroiled in a series of clashes with the White House over a range of issues from nuclear export policy to neutron weapons.

These uncharacteristic strains between Bonn and Washington have become a matter of both public and private concern throughout the Western alliance.

But yesterday Schmidt said under questioning that relations between the two countries "do not depend on the personalities or the parties governing in either country. Our relations right now are characterized on the one hand by an undoubted friendship and partnership.

"On the other hand, from time to time points of divergence may arise."

In effect, Schmidt portrays the reationship with the United States as one that has matured and one in which West Germany has become both more mature and selfconfident. "I'm confident we are going to prove again we are able to solve such problems" Schmidt said.

Still, the recent battles with the White House plus recurring concern expressed in the press here and in some political circles about Communists in Italy, leftist alliances in France and a weakened England have given rise to questions about whether this prosperous and generally conservative country might eventually become alienated from its traditional postwar allies and politics.

Schmidt rejects such notions as unrealistic. In the early postwar years, he said, "Germans almost unconditionally" had to accept help and advice from the Western victors of Hitler's war. Ten years later, Germany had joined NATO and helped found the European Common Market. By the 1960s, further economic and defense development led to growing self esteem, which nevertheless remained far behind that of many oher nations."

"As we approach the end of the 1970s, the Federal Republic has again grown," Schmidt said. "Economically the rest of the world regards us as having grown up. Some would believe too much. There are a few people in many Western and Eastern countries who remain captured by old cliches" about Germany and some who "cultivate those clitches because they don't like the economic weight, for instance, of my country."

"In the thirty years beginning with the Marshall Plan and the Berlin airlift the Germans have never hesitated or nurtured any doubt about their future being tied inseparably to the Americans . . . and at the same time to the understanding that Germany can only peacefully co-exist within a West European community," Schmidt said.

"There is no change in that belief," he said, though he adds that "I would forsee that many German generations to come will not give up the desire to be as one nation and live under one house," a reference to the postwar divisions which have separated this country into Western and Communist nations.

"The world did not witness . . . nor need it fear . . . the rebirth of German nationalist," Schmidt says of his country today. Rather, it is witnessing "the normal development of self-confidence in Germany as would take place in any other nation."

The chancellor pauses between answers, taps some brown powdered snuff expertly onto the back of his hand, and inhales it. He is the most famous of West Germany's 600,000 "schnuofers," or snuff-takers.

Schmidt is a pragmatist, a trained economist and manager who is sometimes outspoken, intellectually impatient yet highly respected. But he also draws criticism from some as a leader without a long-range vision for this increasingly powerful country that also has perhaps more than the usual dose of identification problems with its history.

"Let me state frankly," he says to such criticism, "that I have always been doubtful about political leaders who promote visions.

"We have in this century seen at least two periods of shall we say visionism in German leaders - Kaiser Wilhelm II and the second one much worse. Both lead to catastrophic results.

"I do believe in solid, step-by-step progress in economic and international fields. I think we have shown we were able to establish a rather solid, stable democratic process in this country and a well accepted and very dependable social order.

"I'm not a visionary and I'm skeptical of all the visionaries. The Germans have an enormous capability for idealism and for the perversion of idealism.

Schmidt was cautious when asked to assess European concerns about the generally poor state of U.S. Soviet relations these days.

Maintaining the balance of power is the most important thing, he said. But in a remark that may reflect a wider European concern about an unpredictable White House these days, Schmidt added that "the second most important condition for maintaining peace seems to lie in the political and military leaders in both capitals being able to understand the thinking and the actions of the other party as reasonable and calculable."

"It would be a great menace not only to the two major powers but to the rest of the world if by toppling the balance or by miscalculating or misunderstanding they would allow each other to lapse back into the Cold War," he said.

The most immediate menace in Schmidt's view, however, is what he calls the "enormous worldwide monetary turbulence,

The dramatic fall invalue of the dollar here, the outlay of more than $7 billion thus far by the West German central bank to try and prop-up the dollar, and the fact that some 70 percent of West German exports are in one way or another linked to dollar contracts, has sparked widespread rumors that the Europeans under Schmidt's prodding - will try to broaden their own monetary intergration to try to protect any one currency against the American money's weakness.

Schmidt declines to say precisely where any such plans stand, but he now talks about the possibility of "a convoy" of European Common Market currencies that might also relieve the pressure on the Dollar while protecting each other.

Schmidt said there is no intention to replace the dollar as the world's reserve currency but "what is necessary is to shield the Common Market and employment against monetary turbulence which stems from outside Europe.We must not let our growth policies be destroyed piecemeal by monetary ruptures and uncertanties.