THE cutoff of Soviet assistance to Cuba marks the end of an era. The Cuban revolution may find a way to carry forth, but more privation is inevitable, and Cuba's people are unlikely to suffer stoically for a goal that seems ever more elusive. It is a sobering moment for the Left, both here and in Latin America, which has looked steadily to Cuba for inspiration and found it, but has rarely evaluated the experience in all its complexity.Cuba's many successes and failures in building a just society reflect the limits and opportunities of the cold war: on one side the unrelenting hostility of the United States toward the Castro regime, and, on the other, the ability to play one superpower off against the other. But they also reflect the conceptions that have guided the Latin American Left since it emerged as an organized force in the 1920s. These notions, epitomized by official Cuban rhetoric and still dominant in Left thinking, may once have fit the world; they no longer do. It now seems evident that socialism cannot be built without democracy. State power provides an important means for transforming society, but without increasing grass-roots participation, over the long term defending state power becomes an end in itself, the primary end, and building socialism the means to achieve it. This "socialism" then becomes more form than content, less able to transform the values by which people live. The Cuban government is not as distanced from its people as was the Soviet regim e. But to the degree that political and economic decisionmaking is removed from the people - and it clearly is - socialist forms fail to change capitalist values and only reinforce the state's vain urge to repress them. Revolution can't make a clean break with capitalism by nationalizing property and decreeing that the economy function by a socialist law of value. The dominance of the world economy has not allowed Cuba (or the USSR) to escape the tyranny of the bottom line. Profit, even though it be public, continues to make or break the economy. And the logic of capitalism can't be kept from permeating society. When socialists are in the government, they have to govern the economy by the rules of capitalism. To change these, the Left has to be an independent democratic grass-roots movement at the same time. If not, to one degree or another, it becomes the administrator of an order that it cannot change and in the end accepts. The old standard, "The more we produce today, the more we can distribute tomorrow," is not true. The system does not function that way. The system generates inequality. The Left has traditionally assumed that within the logic of capitalism itself, there was a basis for the emergence of socialism, that the working class had the historic destiny of transforming society. Neither the working class, nor the peasantry, nor the bourgeoisie for that matter turned out to be what the Left imagined. Perhaps capitalism doesn't lead to anything but its own reproduction. Perhaps elements of resistance grow, not as a product of the system's logic, but as the result of something which refuses to enter into that logic. The action of the Left, in and out of power, could then be understood as that which questions the system, keeps open the possibilities for freedom, justice, equality. But it would not prefigure a counter-society. Anti-capitalism is a critique, not an alternative. Profound reforms can make for revolutionary change, but these do not lead toward some ideal goal. Perhaps we should look at revolution as a process of changing people's mentality, a countercultural force that operates on a multitude of planes to redefine what is perceived as right and natural. This is not to say that socialism is dead, or even Marxism for that matter. In fact, all this can be found in Marx. Nor is it to say that Cuba has "failed." Only that without democracy, the Cuban revolution looks less and less revolutionary. One of the signs of the weakness of the Left is its unwillingness to discuss the experience of the Soviet bloc. The Left still can't talk openly about Cuba, because any criticism is viewed as giving a hand to imperialism - the notion that dirty laundry should be washed at home, that to the world the Left must appear as pure. This thinking is bankrupt. Now is the time to defend Cuba. But not by stifling criticism of Cuban policies, on the island and off. Frank and open debate is the best defense against the imperial designs of the US. And it is the only way to breathe life into Cuban socialism. The wall that contained the debate of the Left - the existence of the socialist camp - has disappeared. Painful as it is for many, this too is a liberation, a historic opportunity that may well give rise to new thinking, new movements, a new socialism.