LESTER THUROW's elegantly reasoned interpretation of American economic troubles is an excellent example of a depressing genre -- powerful diagnosis joined to feeble therapy. A professor of economics at MIT, Thurow is also an excellent journalist who recently served an educational term on The New York Times' editorial board. He has written this volume around the notion of zero-sum games in which losses and gains cancel out. Poker is such a game because at the end of the evening the playes' cash has been redistributed but neither increased nor decreased. In the most recent Super Bowl, the Pittsburgh Steelers' winning margin precisely matched the Los Angeles Rams' point deficit.

In economics which grow rapidly, office holders confront each year the singularly pleasing problem of allocating additions to gross national product among various groups of claimants. Until Vietnam sopped up an increasing proportion of growth and severely damaged public confidence in presidents and smaller political fry, it was possible during the '60s to fight the war against poverty and cut personal and corporate income taxes, the neat trick Lyndon Johnson turned in 1964 and 1965. However, once growth slows, it is much harder to play on the national stage these positive sum games in which everybody or almost everybody wins something. We are good, says Thurow, at allocating gains but horrible at sharing out losses. Slow or zero growth implies that what some gain, others lose. Why, scream the latter, should they suffer while others prosper?

On the record, four presidents -- Johnson, Nixon, Ford, and Carter -- have failed to answer that question to the satisfaction either of the voters or their representaties in Congress. More than six years have elapsed since OPEC sprang its trap in October 1973 and still, effective energy policy eludes us because we can't make up our minds how to allocate such a policy's inevitable losses. Oil from shale or coal from Wyoming would improve the situation of New England and middle western energy consumers. It would also damage the natural beauty of the West and deprive western farmers and stock raisers of vital water and range land. Upshot: no action. Or, in Thurow's words, "Technologically energy independence is well within our reach. Politically it may not be within our reach at all."

For one thing, all the players have acquired the capacity to stall indefinitely policies and changes they oppose. By the time Exxon or once of its gigantic peers has beaten down environmental oppositon to the construction of a new refinery, its costs are likely to have risen beyond the stage of financial feasibility. As with refineries, so also with nuclear or even conventionally fueled electric generating facilities and other environmental suspect factories and installations.

Wherever he turns, Thurow sees the malevolent impact of zero-sum calculation. Deregulation of trucking, for example, would attract new entrants who would surely drive down the transportation costs of foods, raw materials and finished goods and thus appreciably slow inflation. But, by the same token, deregulation threatens the profits of entrenched trucking firms and the high wages and benefits now enjoyed by teamsters.

Very much like the veto groups beloved of political scientists, each of Thurow's organized interests can stall action of general public merit even though it usually cannot enforce a program of its own. Producers almost invariably defeat consumers because the stakes for them are much greater. Several hundred steeelworkers may in the aggregate have no more to lose when the obsolete plant in which they labor finally shuts down than 225 million Americans have to gain from paying less for all the products in which steel enters. But each steelworker stands to lose a lot more than a stray consumer gains.

Ideology and self-interest frequently clash. We all like competition and stable prices -- in general. But, Thurow argues, we also demand protection for our own income, job, neighborhood. Almost always politicians heed the urgent, anguished cries of concentrated, special interests who, if aggrieved, are capable of retiring an offering congressperson to private life.

As these special protections and indulgences have multiplied, competition has been hampered, investment in efficient industries has slowed, and growth rates in the United States have fallen calamitously below those of Japan and West Germany. Just to make matters worse, it is precisely because of our growth has been so slow and our unemployment rates so high, that pressures from apprehensive business and labor groups have mounted.

What is to be done? Thurow's proposed remedies, compressed into a brief final chapter, are intellectually fresh and politically implausible in the light of all that Thurow has for 200 pages been saying about zero-sum group conflict. His program includes deregulation of energy, heavy government investment after the Japanese model in growing industries and proceses, elimination of the corporate income tax as part of a drastic and equitable revision of the tax code, and federal guarantee of full employment via a huge and permanent job creation commitment.

Until today the public has resisted higher gasoline prices. How on earth are they to be converted to Thurow's dramatic agenda, even if each item on it were less subject to violent debate? Let not these carping words detract from the quality of Thurow's inspection of our disordered economy. It is a first-rate job. Would that Thurow's powers had not faltered on the threshold of plausible political action.