The coughing, shuffling and scraping you hear in the background is the sound of Ronald Reagan's critics adjusting their positions to his success at Geneva. In drawing the Russians back to a businesslike manner, to Geneva and to arms control talks, he did what many critics on his left thought he could not do. His doctrinal anti-communism, his coolness to arms control, his wild rearmament and his indulgence of administration hard-liners, they felt, might well have kept him and us bemired.

Actually, he did it -- although he did not say so at his news conference -- with a little help from some of these critics. Like bees who sting once and die, they may have a diminishing relevance in our current policy debate. But they did apply a useful part of the pressure to which the president was responding last year when he authorized Secretary of State George Shultz to try to put some pieces of the fragmented Soviet-American relationship back together again.

But it was not just the freezers and "peace" people throwing themselves on the wire, and the State Department and National Security Council officials looking for a reasonable path, who played a role. So did the Pentagon and those other growly hard-liners on the Hill. By setting demanding standards for a return to the table -- in a sense, by being beastly -- they strengthened Shultz's Geneva hand: he could come on as the reasonable alternative.

The portrayal of the Pentagon's Richard Perle by American critics as a powerful nemesis of sound policy, for instance, did two things: it energized the Soviet propaganda machine and helped induce Soviet policy-makers to look to other players among the ranks of the Reaganites as possible partners.

What I suspect was the single most important element producing the Geneva result, however, was a Reagan decision to meet Soviet anxiety about "Star Wars" part way. Granted, the attention given Soviet anxiety is not what it used to be, now that almost everyone sees that the Kremlin piled an immense amount of theatrical hysteria -- now conveniently set aside -- atop its concern about Reagan's earlier policy.

Still, Soviet concern about "Star Wars," as a symbol and vehicle of American scientific mastery if not as an actual coming weapons system, is real enough. Reagan had to give Andrei Groreign minister could carry home, and he did, though it's not clear exactly what it amounts to. Be prepared to hear the American growlies cry that he gave away the store. Maybe some Russians, hearing them, will feel better for it.

The dimensions of this success, of course, need to be carefully calibrated. At the least, it merely puts the United States and the Soviet Union back where they were when Soviet- American relations went off the rail some five years ago. That is no small feat, but there is no ignoring that we and the Russians are returning to a forum of dubious achievements and maximal potential frustrations -- to, say the true doubters, a poker table we've always lost at. Hold the champagne.

At the most, Geneva puts the two countries back where they were five years ago -- but this time perhaps with their eyes open wider. We can hope Moscow realizes the foolishness of having tried to take advantage of Third World windfalls and arms accord loopholes at a moment of America's post-Vietnam distraction: Americans play catch-up with a vengeance. The same history perhaps has taught most of us the wages of distraction.

Do we now, however, risk fresh error? I refer to the possibility that Reagan, having in effect just had Moscow validate his policy of hanging tough, will hang too tough and dissipate his newly gained advantages in bargaining strength and political support.

Granted, from what we know of Geneva, Reagan did not hang "too tough." He let Gromyko out of the corner that the new boy, Mikhail Gorbachev, had painted Soviet policy into by insisting the United States had to call off "Star Wars" or else. The release suggests a capacity for arbitrating between State and Defense, and a feel for negotiating with the Kremlin, that, I confess, I was not sure Reagan was up to.

Reagan will certainly argue, when Congress starts pressing him on some of the sensitive weapons and testing votes, that Geneva has established his diplomatic credentials. He's got a better case than he had a week ago, but lots of people, including me, will want to think more about it. Plenty of harsh negotiating tests are coming, each of them perhaps harder than the one that went before.