Clark Clifford is widely acknowledged to be one of Washington's wise men, truly an elder statesman. Recently he met with several foreign-policy experts who asserted that ''the relationship between the United States and the Soviet Union is worse today than it has ever been since the close of World War II.''
Added Clifford: ''I believe that. And I think it is the most regrettable development of the last three years.'' ''For the first time,'' Clifford said, his knowledgeable informants were telling him the Soviets ''now regard the US as their enemy.'' Clifford said this all stems directly from the President's belligerent rhetoric and his failure to pursue closer ties with the Soviets.
On the surface the Reagan administration continues to take the position that ''talking tough'' to Moscow is the only way to pave the road to peace. ''It's the only language the Communists understand,'' is the way Reagan people often put it.
Richard Nixon talked that way in his earlier years as a congressman and senator. But as President, Nixon moderated his rhetoric and led the nation to better relations with the Communists by opening the door to mainland China and bringing about detente with the Soviets.
Behind the scenes a new administration attitude toward the Soviets is apparently gaining ground. There is considerable anxiety being expressed privately among some of Reagan's top associates over whether the Soviets will come back to the arms-negotiation table. They are coming to believe that the Soviets are not, as anticipated, bending or breaking under the barrage of US firmness - but that, instead, a cold polarization is taking place between the two powers.
Clifford believes that this administration should be worried. ''All through the time I've been in Washington,'' he said, ''I have felt that maybe the major responsibility of an American president is to find a way of getting along with the Soviet Union. As far as I can tell every other president up to now has made an effort in that regard.
''Our attitudes are different; our systems are different; our ideologies are miles apart. But you've got to try to get along with them.''
Actually, the President has been toning down the rhetoric he applies to the Soviets. Beyond that the Reagan people quietly angled for a summit with Yuri Andropov which, if held, would provide the opportunity for the two leaders to get to know each other and perhaps warm up personal if not national relations.
But that was before Andropov's disappearance from public view and the recent heightening of tensions between the nations. Thus when this same Reagan aide was asked about the possibility of a summit, he said the prospects had ''somewhat decreased.'' But he made it clear that the President would still welcome a get-together with Soviet leadership - with Andropov or, if it turned out that way, with a successor.
When asked publicly about the possibility of a summit at a recent mini-press conference, the President said that there would have to be a prepared agenda set up with progressive results assured before he would agree to such a meeting.
That's his public posture. Privately, the President is known to feel that a personal meeting with Soviet leadership could lead to better relations - and at the very least break the ice forming between the two nations.
So it appears that the President, perhaps a la Nixon, is shifting his ground. Not a complete change, of course. He still stays firmly behind his arms buildup. But he seems to be hoping for some concession from the Soviets that will make the full deployment of the Pershing missiles in Europe unnecessary. And he obviously is ready to talk and reason with the Soviets in order to end any possibility of a return to an all-out cold-war period.