When the Communist elite gathered here for their 27th party congress, Mikhail Gorbachev outlined the historic challenge facing the Soviet system. The country was at a crucial turning point, he said, threatened by social decay and economic stagnation.

His predecessors, Gorbachev said, had debated "how to improve things without changing anything." But he was determined to make real changes. And by the time the 5,000 delegates went home two weeks later, they had duly endorsed the new leader's program calling for "radical reforms" to revitalize the economy and society.

Gorbachev's performance was a triumph of politics rather than substance. For by the close of the congress, the details of his "radical" changes remained elusive -- and couched in language expressing a general direction rather than specific policies.

The party congress suggested that Gorbachev may be trimming his sails slightly as he completes his first year in power. Like many an American politician, he is discovering that it is easier to run a political campaign -- or in Gorbachev's case, a political purge -- than to change the policies of a hidebound and bureaucratic government.

Speeches and other evidence from the party congress portray a Soviet leader who is lowering his sights, moderating his rhetoric, trimming his ambitious reform plans to fit the reality of Soviet society.

Gorbachev is treading a familiar path. Quest for change is not new in Russia and many rulers, from tsars to general secretaries, have tried to reform things. One has only to look back in time to see similar problems, dilemmas and preoccupations recurring throughout Russian history. In each instance, the state was the agent of change -- and so it remains.

Gorbachev's "reform from above" has a different tone than the campaigns of his predecessors. He is trying to mobilize the country by talking about the requirements of economic necessity, rather than dreams of mother Russia or communist glory. But he faces the same basic obstacle that humbled tsars and party chiefs: the very obduracy of the Russian people and their way of life. To succeed he must alter the way Russians think and live.

So how realistic are the expectations among party officials here that Gorbachev's accession to power foreshadows a basic transformation of Soviet life? Was the congress merely a "Gorbat-show," to borrow a phrase coined by the French newspaper Liberation, or did it mark a decisive change in policy? Assuming that Gorbachev genuinely wants change, will he be blocked by the Soviet ideological and political legacy and the nature of the country he leads? Or does he have special skills and insights that might allow him to carry out his vision?

Answers to these questions may not be clear for years, or even decades. However, several basic facts are already evident. Gorbachev is a gifted politician, trained in the roughest school imaginable, but he seems to be less skilled as an ideological or economic thinker. At the center of his vision of economic change, there is an ill-defined and perhaps empty core. He is a strong and decisive administrator, but thus far he has chosen to balance the innovators on his team with solid party men -- at the cost of losing some of the aura of dynamism and reform.

The final point about Gorbachev is that he is lucky. So far everything has broken right for him. His mentor, Yuri Andropov, initiated the process of change that permitted Gorbachev to move so quickly and decisively on so many fronts. In the twelve months since he took power, Gorbachev and his men have remade the Politburo, removed virtually all potential opponents at the top and purged a startling 82,000 party officials at lower levels -- about one fifth of the party bureaucracy.

An example of Gorbachev's good fortune is the fact that the congress itself came so early in his tenure. This allowed him to install his own central committee rather than work with the men and the policies of his predecessors. It legitimized his program. Moreover, the ritual of the congress helped restore the confidence and sense of direction of a Soviet establishment that had been shaken by the events of the last few years.

All in all, it was a remarkable political performance. Gorbachev proved himself adept at balancing political interests. At the congress, he took the middle ground between his ideological chief, Yegor Ligachev, whose pronouncements have a distinctly conservative tinge, and his latest protege, Boris Yeltsyn, the Moscow party chief, who is the most outspoken advocate of radical changes. The sight of these two men at the congress, both of them close to the leader, seemed designed to reassure different elements in the elite that future reforms would be prudent, that nothing would be done precipitously, that Gorbachev would loosen the system but not go so far as to provoke a political cataclysm.

There wasn't perfect harmony at the party congress. While Gorbachev dominated the proceedings there were other voices making different points. Indeed, the general secretary himself made clear that there were doubts within the establishment about the scope and pace of his program when he said that that some people believed that "any change in the economic mechanism constituted a deviation from socialism."

Gorbachev's problem now is translating his evident political skills into policy. Quite clearly, the new leadership does not yet have a coherent plan of action for the social and economic transformation. And it is equally clear that if and when such a plan emerges, it will confront a vast reservoir of resistence at many levels. Soviet society moves slowly and it takes a long time, even under the best of circumstances, for government decisions to be translated into action. Frequently they simply disappear in the bowels of the byzantine bureaucracy.

Bureaucracy is only a part of the problem. A greater obstacle may be the apathetic and cynical Soviet population, which enjoys the benefits of a low-grade welfare state and is wary of losing them. Most people eagerly favor economic changes as long as they do not affect the low costs of housing, heating, food, transportation and free medical care, education and other services -- all of which are subsidized by the state.

To shake up this stolid society, reformers are thinking about some previously unthinkable issues, such as market-type pricing. Many officials understand that the key to meaningful reforms is the pricing system; changing it would open the way for using economic levers throughout the economy -- and would begin to take the government out of the business of subsidizing virtually everything in this country.

Nothing much was said about reforms of the pricing system at the congress. But economist Abel Aganbegian, who is a Gorbachev advisor, told journalists that he advocated the elimination of government subsidies across the board -- except in certain welfare areas such as child support, assistance to the elderly and medical services. But, Aganbegian said, such changes shouldn't be expected in the near future.

Only in agriculture are the Soviets likely to make modest reforms of the price system anytime soon. The new leadership intends to allow the peasants to sell most of their grain and produce at whatever prices they can obtain, except for a small amount to be sold at fixed prices to the state.

Senior officials admit that the reform timetable is slow. They say privately that the next five years will see only gradual changes and experimentation in preparation for Gorbachev's "radical" steps. They argue that more time is needed to prepare the way for introduction of these reforms, including efforts by the party to update its ideological and political image.

To use Gorbachev's own words, the party has to "blend the grandeur of our aims with our real capabilities." The implication here is that the previous plans were based on misreadings of Soviet capabilities. So far, the net result of this "blending" has been a scaling down of the Kremlin's messianic ambitions, a retreat from the Bolshevik utopianism, a more realistic assessment of international relations, and an important adjustment of the dogma.

Nothing better illuminates the scope of the Kremlin's ideological ferment than Gorbachev's revised party program.

The old program, which was drafted by Nikita Khrushchev in 1961, predicted that the second half of the 20th century would be a period of "struggle" between imperialism, led by the United States, and communism and socialism, led by the Soviet Union; this struggle, the program said, would result in the "downfall of imperialism" and ultimately lead to "the triumph of socialism and communism on a worldwide scale."

The 1986 revision drops the concept of struggle between the two systems. The current period is one of a "historic competition" between them; instead of the promised "triumph" of communism, there is a more ambiguous phrase holding out hopes that "mankind's movement toward socialism and communism" cannot be reversed.

The vague new phrases of the revised program acknowledge the chasm between Moscow's communist aims and its "real capabilities," suggesting that the new generation of Russians regards the world as less simple than it once seemed, and that they want to pursue Soviet national interests in ways that maintain a balance of power and peace.

The Soviets are also toning down their references to Lenin's dream of revolutionizing and reordering the world. The new line seems to be that Lenin's declaration of war against bourgeois societies everywhere is suicidal in the world of nuclear weapons. Gorbachev explicitly asserted that the Soviet Union was no longer in the business of "stimulating revolutions" in other parts of the world.

The new leadership seems eager to convey the notion that the Soviet Union now wants to behave like any other country of its power and size -- and that communism's "manifest destiny" is to improve the quality of life in Russia rather than work to overthrow bourgeois societies.

For the new Soviet generation, communism has become a distant and largely theoretical goal. The Russians don't maintain any longer that the Soviet model is the only correct one. There are, Gorbachev declared, "endless variations of socialism but they have one general objective."

The rhetorical adjustment made by the Kremlin at the congress capped nearly six years of political disarray. An accumulation of domestic and foreign problems had produced widespread disillusionment and discontent. At home, the faltering economy was heading toward a crisis, with declining growth rates, a series of agricultural disasters, widespread corruption and gross inefficiency. Abroad, Brezhnev's policies had begun to unravel. The old guard seemed unable, both physically and emotionally, to deal with these problems.

This tide of misfortune produced the obvious signs of social decay -- corruption, inefficiency, alcoholism, lack of initiative and enterprise. It also infected the Soviet establishment with a massive doze of political cynicism and apathy that paralyzed its will. The party was holding power for the sake of holding power. The system was at a standstill. Gorbachev and his men came to power with the explicit commitment to reverse this trend of economic decline, policy drift and leadership paralysis.

The 27th congress marked the end of this period and the first normal generational change in Soviet history, one that brought to the fore men and women who had few links to the past leadership and thus no responsibility for the previous mistakes. As a result, Gorbachev and his confederates had no need to look for excuses; unlike Khrushchev, Gorbachev did not have to make a "secret speech" or denounce his predecessors. The very course of events during the past six years had condemned the old guard.

The new Kremlin team includes people who are very different from the old guard. They are better educated and saw the outside world as relatively junior officials, but they were not involved in the shaping of foreign policy. They possessed intimate knowledge of the domestic scene because virtually all of them made their careers in the provinces. Given their backgrounds, the new leaders fully understood the nature of the crisis into which the society had plunged in the early 1980s. This made it easier for them to grasp, as one senior official put it privately, that the country faced the choice of either accepting the challenge of a national reconstruction or accepting defeat.

Gorbachev's relatively calm analysis of the Soviet situation stems from one ironic legacy of the Brezhnev years: the achievement of strategic parity with the United States. There is a belief here that no significant changes in the strategic balance are possible for the rest of this century despite what the Soviets see as American efforts to gain superiority. The confidence that they can maintain an essential equivalence in strategic weapons reinforced the new leadership's focus on internal problems. And there is a conviction here that the real strategic danger for the Soviet Union is an inefficient economy incapable of entering the hi-tech age.

What this means is a reorganization of the economy. Moscow's participation in the arms race and the huge costs involved in achieving parity had left the country with a split economy -- military and civilian -- with the military claiming the best of everything. Gorbachev's objective is to have one single economy.

Gorbachev's strategy can be described as economic de-Stalinization. He believes that the Soviet system, although a superior form of social and economic organization, has failed to develop its true potential because it was based on the principle of coercion. This coercive aspect deformed the system, although it performed well during a series of crises -- the civil war, industrialization, world war two, and post-war reconstruction. "We thought that we could go on forever like this," one high official conceded privately.

It was difficult for the old guard to grasp that everything was changing and that force, while effective in earlier periods, was no longer an efficient stimulus in the hi-tech age. "We also reached another conclusion, the conclusion that shocked many of us, I should add," the official continued. "That conclusion is that we cannot develop our economy without democratizing our society. Democratization is the basis for an accelerated economic development."

How this "democratization" fits into the scheme of things contemplated by the new leaders is not quite clear. Gorbachev has talked about workers' participation in the decision-making process at the work place. He has also made vague references to the concepts of supply and demand, devolution of managerial authority, realistic prices and modernization of the financial and banking systems. All these economic levers are to be applied "within the socialist context" -- but how that is to be done remains unclear.

Judging by the course of the debate, there are three types of reforms considered by the Kremlin -- policy reforms, organizational reforms and structural reforms. Gorbachev seemed to have embraced all three. But for him, what is economically desirable must be tempered by what is politically possible. Hence the pace of changes is bound to be slow and gradual.

Whether Gorbachev can succeed remains an open question. His country is eternal and in many ways unchanging. Communism as a system in Russia seems to be exhausted; short of a dramatic infusion of fresh ideas and new approaches and initatives, it seems to face the prospect of decay. This is thoroughly understood in Moscow, and it helps explain why Gorbachev describes his task as "titanic."