Millions of radicals, leftists, socialists and anti-imperialists around the world will be saddened by the announcement of the death of the leader of the Cuban revolution, Fidel Castro, at the age of 90. He will, obviously, be particularly mourned in much of Latin America, Africa and other parts of the “third world” that identified with his defiance of US imperialism.

The story of the Cuban revolution and its two main leaders, Castro and Che Guevara, is both romantic and genuinely heroic. A group of only 82 guerrillas, led by Fidel, sailed in a small boat, the Granma, from eastern Mexico and landed on the coast of Cuba on 2 December 1956. They were immediately attacked by the Cuban air force, suffered numerous casualties and were scattered. When they eventually regrouped in the Sierra Maestra mountains, their numbers were reduced to 12. Yet two years later, January 1959, Batista, the corrupt and brutal dictator, fled Cuba and Castro’s revolutionary army marched in triumph into Havana.

At first, Castro and his movement were democratic nationalists not socialists or communists. But hostility from the old Cuban ruling class and US imperialism pushed Castro and Cuba into nationalisation of various industries and into the Soviet camp. Castro in 1961 announced that the Cuban revolution was a socialist one.

This story alone would have been inspiring to millions at the time of anti-imperialist revolt around the world, the Vietnam War and the struggles of the sixties. Two other achievements also stood to Castro’s credit and secured his status. First, his and his regime’s survival in the face of 50 years of relentless pressure from the US – pressure that ranged from military intervention at the Bay of Pigs in 1961, attempted assassinations by the CIA, to economic and travel embargos. Second, there was Cuba’s establishment of decent public health and education, in marked contrast to other Caribbean and Latin American states and indeed the USA itself.

However, there were serious problems, inherent from its inception, in both the Cuban revolution and in the Cuban revolutionary regime.

For socialists, as for Marx himself, socialist revolution is the act of the working class itself – it is a process of self-emancipation in which working people take control of society and run it democratically in their own interests. This did not happen in Cuba. Rather, Castro’s small guerrilla army acted “on behalf of the people” and established, together with the old Cuban Communist Party, its rule from above. This became, and remained, a one-party state with no real democracy and very little political freedom. It was a state capitalist rather than a real socialist society.

There was also a major difficulty involved in the isolation of the Cuban Revolution and its dependence on the Soviet Union. In this state of siege, Cuba remained trapped in poverty and unable to develop effectively. And when the Soviet Union collapsed in 1991, its support for Cuba was withdrawn and the economy was plunged into crisis, which it barely survived and from which it has never fully recovered. This has pushed it back towards rapprochement with the US and Western capitalism.

Again socialists, beginning with Marx, have always understood while a revolution can begin in one country the successful building of socialism has to be international: the revolution has to spread to other countries. The idea of building socialism in one country was the invention of Joseph Stalin in 1924 and used to legitimise the establishment of his own dictatorship.

Castro’s comrade, Che Guevara, understood the need to spread the Cuban revolution and, with great heroism, undertook the task. But the attempt failed. Guevara’s method was to try to repeat in Bolivia the guerrilla struggle in the mountains that had worked in Cuba. But the US had at first thought it could work with Castro and did not mobilise to defeat his movement in its early stages – they did not repeat this error in Bolivia, or elsewhere in Latin America where guerrilla struggles were launched. Che was captured and murdered in 1967 and there was no repetition of the Cuban victory. Consequently, Cuba remained isolated and impoverished.

Today, uncritical supporters of Cuba and those who hero-worship Castro will blame these problems on the US, which is fair enough, and compare Cuba favourably to its neighbours Haiti and Jamaica etc. which is also reasonable. But they will also tend to turn a blind eye to the lack of democracy and political freedom, the long standing oppression of LGBT people, the continuing class divisions and inequality and increasing accommodation with the US. This is mistaken.

Socialists today can recognise Castro’s achievements while also explaining that we have a very different conception of socialism as a real people’s democracy of equality and freedom based on workers’ control of workplaces and communities.