Disturbing premonitions of war now sweeping over Europe have brought its neutralists out of hiding; at the same time their mirror-image American isolationists are, like 17- year locusts, re-emerging from a long underground slumber. The neutralists are chanting their old theme about staying aloof from the battle; our reborn isolationists are singing their nostalgic anti-European tune. But, though the melodies are familiar, the words on both sides are subtly different; the keening of the neutralists has petulant anti-American overtones, while, during their long hibernation, the isolationists suffered a critical mutation. Unlike their predecessors of the '30s who wished to avoid entanglement in a great-power conflict, our mutated isolationists seem to be spoiling for such a conflict --demanding that if Europeans do not comply unquestioningly with our anti-Soviet policies we should go our own way, free from the constraints of moderation to stand alone against the Soviet aggressor.

All this comes into focus as the Western nations try to shape a common policy toward the Polish crisis. The neutralists of Europe see the rape of Poland as primarily an internal affair of the Communist Bloc; they are reluctant to challenge the division of Europe sanctified by the Helsinki Agreement and the unintended consequences of Yalta. Our isolationists, on the other hand, would like to bring that whole system down.

It is the familiar paradox: liberal elements wish to avoid change while so-called conservatives seek radical solutions. As is so often the case, the radical view has been best articulated outside the government by a group of mutated isolationists dominated by well-known American neo-conservatives. That group, which modestly calls itself The Committee for the Free World, has recently published a manifesto declaring the Polish crisis to be a splendid opportunity to recognize "the illusions of d,etente for what they are." It considers it absurd to believe that the West could effectively "use economic pressure to force the Polish government to restore the freedoms now taken away"; instead, it implies that we must somehow break the hold of the Soviets over Eastern Europe--or, in other words, achieve what John Foster Dulles called "liberating" the satellite countries.

The committee proposes to achieve that purpose by denying to Poland and the Soviet Union "Western loans, Western grain, and above all Western technology." Through these means, it contends, we can "at no risk of military conf ontation . . . further the processes of disintegration from within that may mark the beginning of the end of the Soviet empire." Thus we can "hasten the day when the world will be free of Soviet imperialism and the totalitarian barbarisms it carries in its wake."

Though the committee poses the issue in the rhetoric of freedom and human rights, it uses those terms only in a specialized anti-Soviet context. Most of its leading members had fiercely opposed Carter's selection of human rights as a major tenet of our foreign policy, and they have led in cheering the Reagan administration's courtship of repressive governments in Argentina, Chile, the Philippines and Turkey and its distressing tolerance for South Africa's bloody- minded racial policies.

The committee's aim of furthering "the disintegration of the Soviet empire" so as to "free the world of Soviet imperialism" strikes directly at the whole system of power in Europe that has prevailed for almost four decades. It would mean allowing the Eastern European nations to make their own arrangements with the West. Though pleasant to contemplate, that prospect holds implications terrifying to most of our European friends. They have lived for a thousand years in a world marked by the rivalries of great powers--first the Hapsburgs against France; then, under Louis XIV and Napoleon, France against the rest of Europe; finally, beginning with Bismarck, Germany against France. Their blood-drenched history has taught them that peace depends on the maintenance of an effective power balance and that war results when that balance is abruptly overturned. Since almost every generation of Europeans has known war and its devastation, it is, therefore, not surprising that many today are wondering if the cycle of peace we have enjoyed for 36 years may not be nearing its end. Quite understandably they see frightening possibilities in the Reagan administration's rejection of diplomacy and its single-minded concentration on military power. Thus the thought of any action that might promote the disintegration of the present power system in an age of nuclear weapons makes the cold European winter even chillier.

President Reagan seems to have shown some understanding of this, for he has reportedly rejected the proposal for strong financial and economic sanctions vigorously urged by mutated isolationists in the administration such as U.N. Ambassador Jeane Kirkpatrick (a member of the committee) joined apparently by Defense Secretary Caspar Weinberger. Though few believe that the "processes of disintegration" now afflicting the Soviet Union are likely to "mark the beginning of the end of the Soviet empire" or that those processes can be seriously "furthered" by the economic measures the committee proposes, the very thought that the American government might be pursuing that objective would drive more and more Europeans into the neutralist camp. They are acutely aware of the Russians' brooding insecurity resulting from two invasions from the West in modern times, and they know that the Soviet Union would never peacefully allow the loss of its Western glacis. One cannot, of course, rule out the hope that time and events will ultimately erode the current European power system, but to avoid world destruction in a nuclear age, change must come gradually. Today, any effort to dismantle that system would, if taken seriously, go far to destroy Western unity and push a frightened Europe toward accommodation with Moscow.