Pity the poor Soviet conservative (or, if there is such a thing, neoconservative.) Russian troops are scheduled to begin withdrawing from Afghanistan this year. For the first time since Lenin arrived at the Finland Station, communism may lose a nation that was in its grasp. The Soviet conservative has an unenviable task: he has to determine who lost Afghanistan.

By comparison, the American conservative has it easy. When it comes to figuring out who lost Vietnam, he shops a mall of scapegoats -- the press, left-wing intellectuals, irresponsible students, naive actresses, an irresolute Congress and, of course, the "San Francisco Democrats" of Jeane Kirkpatrick's vivid imagination. These elements supposedly formed a Fifth Column that did at home what the communists could not do on the battlefield: defeat the United States.

It has taken the Soviets to finally rebut the argument of these Vietnam revisionists. Afghanistan is Russia's Vietnam -- possibly with even greater consequences for the Soviet Union. Its retreat is an epochal event, the culmination of an American policy begun under Jimmy Carter and continued by Ronald Reagan. The march of communism has not only been arrested, it may have been reversed. The Soviet army has been humiliated. Worse from the Russian point of view, the so-called Brezhnev Doctrine has been scrapped: a country once in the communist orbit may slip that noose.

According to American conservatives, the Soviet Union in Afghanistan had all the advantages the United States lacked in Vietnam. Its press was compliant. No Russians demonstrated in Red Square. No Soviet Jane Fonda flew to Afghanistan to denounce her own country. No congress held embarrassing hearings and meddled in foreign policy. In a way, this was the United States, circa 1965, as Norman Podhoretz would have wished it.

So what went wrong? The answers are a double-barreled rebuff to conservative theory. First, the Soviets seem about to do what conservatives insisted they would never do: retreat. Supposedly unrestrained by either domestic opposition or world opinion, the Soviets could apply as much force as needed to win the war. Unlike the United States in Vietnam, the Russians would not be afraid to win. The invasions of Hungary (1956), Czechoslovakia (1968), to cite just two examples, proved the Soviets would do what they had to do. They were, after all, evil. (See Reagan, Ronald, collected speeches thereof.)

As a result, it was never the goal of Reagan administration ideologues to win the war in Afghanistan; that seemed beyond reach. Their intention was to pay the Soviets back a bit for the humiliation of the United States by their clients, the communists of Vietnam. The intent in arming Afghan rebels was to bleed the Soviets. It was, of course, immaterial that Afghans were being bled too (life is not fair; you have to break some eggs to make an omelet). It was equally immaterial that Afghanistan, with U.S. aid, could become an Islamic fundamentalist state as anti-American as the ayatollah's across the border in Iran.

Second, the Soviets confronted the same circumstances we did in Vietnam. They rushed to the aid of an unpopular regime. Afghan communists had introduced atheism into a Moslem society, begun the emancipation of women and, equally repugnant to independent Afghan tribes, were attempting to centralize authority in Kabul. Just as we were pitted against fanatical nationalists in Vietnam, the Soviets were pitted against religious zealots in Afghanistan. The enemy couldn't be defeated; most of the time it couldn't even be found. Jungle was replaced by mountains. The mujaheddin could never win, but neither could the Soviets.

World opinion, supposedly irrelevant to the Soviets, played a telling role in their decision to withdraw from Afghanistan. Proclaimed pal of Third World regimes everywhere, the Russians had nevertheless invaded one of them -- an Islamic one at that. Throughout the Moslem world, the Soviet Union was on the defensive. It could hardly pose as the champion of the Arabs (in contrast to the Israeli-supporting United States), while it was killing Moslems in the Hindu Kush.

The Soviet experience in Afghanistan turned out to be almost identical to the American experience in Vietnam. This was the case even though Russia lacked the American right wing's usual suspects -- all the elements that made up the antiwar movement.

What defeated the Soviet Union in Afghanistan is precisely what defeated the United States in Vietnam: it chose to fight a war in which the price of victory was disproportionate to the potential gains. The Russians learned a lesson in Afghanistan and so, if they think about it, should America's Vietnam revisionists. Somewhere in the Hindu Kush, their argument took a fatal bullet.