SOMETIMES, IN THE world of Soviet-American propaganda wars, one side scores a triumph which goes beyond the usual superficiality and sets people to thinking. So it was for the Soviet Union in the last days of 1986, when 50 Soviet emigres living in the United States voluntarily returned to their native country.

The emigres gave various reasons for their departure, ranging from simple homesickness to plaintive criticisms of American society. Some complained of intense competition and difficulty making ends meet. Others cited a paralyzing fear of crime, while at least one woman expressed concern that her teenage daughter might start using drugs if she stayed in America. In the Soviet Union, she reasoned, her daughter would be safe.

On one level, the event was another example of the increasing sophistication of Soviet propaganda ministers under the leadership of General Secretary Mikhail Gorbachev. Government officials orchestrated the show by reversing a long-standing policy virtually barring the return of emigrants and then scheduling a large group to return on one day. The Soviet press gave heavy play to the arrivals, including some Jews, pronouncing that the sorry souls had found "ruthless competition, the spirit of money-making, crime and drug addiction" in America.

THE CROWING IN Moscow elicited something more than the usual blithe dismissal of Soviet propaganda displays. Instead, some people on this side of the barbed-wire actually paused to consider the anomaly of refugees from totalitarianism repudiating life in America. Though they were not the first Soviet emigres to do an about face, the most recent repatriates made up the largest and most highly publicized group to do so. And even though the 50 represented a tiny fraction of the hundreds of thousands of people who have left Russia in the last two decades, the existence of even a small number of people wanting to return seemed a slap in the face. The whole scenario strained credibility: How could anyone voluntarily give up American freedom for Soviet totalitarianism?

The answer is that under the right circumstances, the trade can be made quite easily. Human beings, for the most part, are not idealogues. What they generally want is to be able to enjoy family, comfort, safety and good health. Though it would be comforting to explain the departure of the 50 Soviets by suggesting that their Soviet upbringing didn't foster the lust for freedom possessed by native-born Americans, the truth is more troubling. For vast numbers of people the government is a trivial, background feature in the daily struggle to attain happiness and security.

True, most Americans seem to believe that life in this country is better than in the Soviet Union because we live under a constitutional, democratic government. But how often does this distinction emerge from the abstract to become a part of daily life? How many Americans ever really test the Constitution by making controversial statements or protesting the status quo? How many exercise freedom of expression by saying or doing things that might be restricted under a different form of government?

Because very few people are inclined to do these things, and because economic and social circumstances imprison many of our citizens who might otherwise be so inclined, our "freedoms" are generally exercised by an extremely small minority of people who participate in the political, artistic and intellectual life of the nation. In rare cases of national upheaval, larger groups mobilize to protest unpopular wars or glaring injustices. But for the most part, if the Constitution were repealed tomorrow, it would be a very long time before the lives of a great number of Americans would be significantly affected--though some would celebrate our new freedom to torture criminals and pray in public school.

This is not so much an attack on the United States as an attempt to explain how those 50 who left in December could make the decision they made. Some were people on the fringes, unable to attain the standard of living that lured them here. Some were frustrated artists who, no longer restrained by government, found they were restrained by an inhospitable market that provided no buyers for their work. Some were plain scared and homesick.

But for the most part, the folks were just normal. Given a choice between poverty, loneliness and fear in a democracy, and relative prosperity, family and safety in a totalitarian regime, the returning Soviets chose the latter. Like most human beings, they eschewed ideology and high ideals for a chance to enjoy life just a bit more than before.