Mr. Reagan has been quick to point to the perils, real and imagined, of Soviet propaganda directed against the democracies. For someone pleased to be known as the "great communicator," however, he has been surprisingly slow to organize his own government to conduct what is called, when the democracies themselves do it, "public diplomacy." Even now, he wants it known that his purpose is "not propaganda-- it's public relations." The distinction may not have everywhere the calming effect he intends.

Still, the president does finally seem to be conquering a traditional and misguided American reluctance to use openly the arts of public persuasion--a field in which democracies ought to have every advantage--to serve American interests abroad. What did it was the replacement of the slow-paced Leonid Brezhnev by the fast-stepping Yuri Andropov, whose campaign to sway European opinion on the missile question is rolling along. Mr. Reagan is now stepping out himself.

Three separate things are going on. The United States Information Agency, whose mission is to articulate American policy abroad, has formally been given a seat at the table where high policy is made, or so it hopes--these welcomes to USIA tend to come and go. Then, an amount of money ($65 million over a few years) has been allotted to the "crusade for freedom" that Mr. Reagan announced last summer in London to help strengthen democratic institutions and groups around the world.

Meanwhile, the media consultant whom Mr. Reagan named ambassador to Ireland, Peter Dailey, has been handed the specific task of selling Mr. Reagan's "zero option." He is to work out with the allies ways to keep their publics behind NATO's commitment to start deploying new American missiles at the end of the year--unless the Soviets agree to take out all the SS20s they have already put in. It's kind of crazy, and not a little distasteful, to have to work on Europeans to accept the very protection against new Soviet missiles that they asked the United States to provide. The fact is, however, that the United States must deal with the two principal fears felt in Europe, the fear of Soviet power and the fear of nuclear war. Otherwise it forfeits leadership of the alliance. Given that Moscow has been deploying new, menacing and strategically excessive missiles against Europe by the hundreds, it should not be all that difficult for Europeans to appreciate the threat posed by Soviet power. The zero option may or may not turn out to be negotiable, but surely its intended result--to relieve all of Europe, including the East, of the shadow of a whole missile class-- cannot fail to appeal to reasonable people. The United States has, in short, a good case.

Any effective "public relations" campaign, however, must also take into account the push Mr. Reagan has given to the Europeans' fear of war--the fear on which Andropov so assiduously plays. The administration has not only spoken too loosely about this tender matter. It has exacerbated it by systematically denigrating the stability of nuclear deterrence and by keeping before the public the thought that the United States might actually have to fight a war. Earlier administrations dealt with essentially the same strategic circumstances without arousing anxieties on the scale Mr. Reagan has stirred. He must find his way.

It is not undercutting Mr. Dailey to note that, in keeping Europe faithful to its NATO commitment, Mr. Reagan is the main man. Through speeches, leaks and silences, by the general manner of his leadership and by the specific way in which he conducts negotiations, he will finally be the American most influential in the way Europe goes.