How dangerous?

Most Western experts on the Soviet Union and on East-West relations are now in agreement that a new, and lower, level has been reached in the relationship between Washington and Moscow.

George Kennan, the senior in experience and years among American Kremlinologists, says (in the New Yorker, Oct. 3) US-USSR relations are today ''in what can only be called a dreadful and dangerous condition.''

Lawrence T. Caldwell (Occidental College) and Robert Legvold (Council on Foreign Relations) say (in the fall issue of Foreign Policy) that ''the trends, frankly, are far more discouraging and potentially dangerous than is understood by many American commentators, who know little of the mood in Moscow.''

William G. Hyland, newly named editor of Foreign Affairs, when pushed on television to say just how dangerous is the present condition, declined to say that it is yet dangerous, but agreed that if present trends continued it could become dangerous.

Some, on the right wing in Washington, favor making relations with Moscow worse than they already are. They favor a revived grain embargo; a tight ban on almost all trade, particularly technological trade; economic cold war; and a break in diplomatic relations.

There is counterpressure from Midwest farmers concerned about grain prices, from domestic elements who consider coexistence with a difficult Soviet Union preferable to nuclear destruction, and from the European allies.

Since pressures seem more or less evenly balanced, the prospect seems to be that President Reagan will try to keep moving along his present course, which is being described these days in Washington as a ''two-track policy.'' That seems to mean hardest possible rhetoric, but continuing to sell all the grain Moscow will accept, maintaining a dialogue about weapons control, and continuing with normal diplomatic relations. In this case normal might be defined as the minimum necessary to keep communication alive.

The essence of the analysis by the experts seems to be that Moscow has decided that there is no longer a real prospect that Mr. Reagan's operating policies will be substantially less hostile to them than his rhetorical posture. They seem to have hardened on the assumption that they can do no serious business with him and at best will just have to sit out the end of his administration.

Mr. Kennan is anxious lest the trend, if unchecked, lead to an actual war. Other experts see less alarming implications. To some, it means only that the relations will be in a deep freeze during the Reagan presidency. This could mean another round of new Soviet weapons, deployment of some new weapon somewhere to balance off deployment of American Pershing and cruise weapons in Europe this fall, and avoidance by the Soviets of any weapons-control agreement.

A Reagan-Andropov summit seems highly unlikely now.

There is another consequence, which seems to me to be quite as undesirable, but has yet to be generally noticed or mentioned.

So far the Western allies are standing on their commitments to the alliance and intending to go along with the new deployment of American weapons in Europe. But around the fringes, there is new talk of possible ways by which the NATO allies could distance themselves from Washington.

In other words, we seem to be back to where we were in early Reagan days when allied diplomats sometimes muttered such thoughts as ''your President frightens us more than do the Russians.''