In the longer run, almost certainly yes. The pressures to liberalise in a country just 90 miles from Florida are immense and surely irresistible.

It was after all, glaring economic failure by comparison to western Europe that led to the uprisings in eastern Europe in the late 1980s, and brought the downfall of communism in the Soviet Union. Without aid from Venezuela and China, Cuba's own economy would be in even direr straits than it is. Castro has made sure that the immediate succession passes to his brother Raul, and there are no serious ideological cracks in the upper echelons of the regime. Dictatorships by nature believe they are eternal . . . but Cuba cannot avoid change.

Raul himself is believed to favour more liberal economic policies. Whether change will be peaceful is anyone's guess.

Opposition to the regime certainly exists.

But it is hard to gauge its extent in a country that has not had an election in half a century, and where the press is so tightly controlled. Nor is it clear how warm will be the welcome for returning exiles, many of whom live in an ideological fantasy land dating back to the 1950s.

Given that 70% of Cubans have never known any other ruler than Castro, it is unlikely that a post-Castro Cuba will slip meekly into the American fold.

What good has Fidel done for Cuba?

The emigre community in the US would answer in a single word, none. They point to the economic problems of the island, its denial of political diversity, and its dreadful human rights record. But the Castro model of socialism can point to achievements as well. Despite its scant resources, Cuba has fashioned education and healthcare systems that would be the envy of far richer countries. Illiteracy has been eradicated, while life expectancy at birth in Cuba is about the same as in the US, despite healthcare spending per capita one 20th the size of that of its giant neighbour. The key has been a localised system of medicine, that puts a heavy emphasis on preventive treatment. More broadly, Castro has given Cuba a real sense of national identity. In this he has been unwittingly helped by the US, whose 45 years of persecution of Cuba have served to strengthen, not weaken, the regime.

What damage has he done?

A great deal, unfortunately. Castro was hugely popular when he swept the former dictator Fulgencio Batista from power in 1959. But the price of "socialism or death" has been the ruthless suppression of personal and political freedoms. Some of Cuba's problems are due to the travel and economic and financial embargo from the US, tightened further by President Bush. The fatal misstep, however, came early on, when Cuba adopted the Soviet model of development, and yoked itself thereafter to Moscow for aid and economic support. The collapse of the Soviet Union was a grievous blow. Since 1991 the country has dabbled in economic liberalisation, and encouraged investment from Europe, Canada, Latin America and most lately China. But it has hit the dilemma faced by every authoritarian regime: how do you free up the system without undermining the monopoly of technology and information on which the regime rests? The fax machine, it is said, helped destroy the Soviet Union. The internet could do the same for Cuba.

How does Cuba's economy compare with Latin America?

A lack of reliable statistics, and the socialist organisation of the economy, make comparisons difficult. The CIA reckons that Cuba's GDP, on a purchasing power parity basis, was about $26bn ( 20bn) in 2002, implying percapita income of about $2,300. The UN's Human Development Report suggests a GDP per capita of $3,600 in 2004. This still compares with $6,230 for Mexico in 2003, according to the World Bank, $4,360 for Chile and $3,860 for Argentina. Among its near neighbours, Cuba comes in below Jamaica but above the Dominican Republic, and far above Haiti, the poorest country in the hemisphere.

Why is Castro such a hero of the European left?

His personal charisma and his resistance to pressure from the United States. In power since 1959, Castro is the longest serving surviving head of government in the world. He has seen off nine US presidents, and if he lasts three more years will see off his present nemesis George Bush. Cuba moreover is, along with North Korea, the last surviving communist state. Eastern Europe cast off communism in 1989, and two years later the Soviet Union, Castro's key if ultimately impatient ally and Cuba's economic patron, also collapsed. But somehow Cuba avoided this fate.

Separately, repression and human rights abuses are somehow easier to overlook in a subtropical setting than in the frozen wastes of Siberia.

Castro's own glamour derives from the revolution and his legendary comrades in arms, first and foremost of course Che Guevara. His trademark green fatigues are an unsubtle reminder of this past.

His lustre has only been increased by the global dislike of this President Bush. Castro is not only an idol of the European hard left. He has never been more popular in Latin America than now. At an economic summit in Argentina last month, the Cuban leader was the unchallenged star of the show.

What part will the US play in what happens?

A huge one, even if Washington formally adopts a hands-off policy. That of course is unlikely. America spent most of the first half of the 20th century interfering in Cuban affairs.

The $80m plan already drawn up to assist Cuba's transition to democracy confirms the US has every intention of doing so again.

But even a partial lifting of sanctions could help Cuba's beleaguered middle class, and give a huge lift to reformers.

Restricted as they are, financial remittances from the Cuban-American community are a vital support of the island's economy.