RAÚL CASTRO has been handed power by his elder brother Fidel, the world’s longest-serving leader, with a promptness of which Gordon Brown or the Prince of Wales can only dream.

Even if the handover is temporary in name, as Fidel Castro maintains, many reckon it will be permanent in effect, as the iconic leader’s health fails.

For all Fidel’s well-advertised preparations for this shift, which has been uncertain only in its timing, it may not secure his legacy as he intends. But neither may it open the door to the reforms which Cubans desperately want. The risk for Cuba is that Raúl will prove an awkward and unpopular leader: a paler copy of Fidel without the charisma. Many fear that he has a greater propensity for brutal repression than his brother, and a more limited vision, which could set the island on the path to violent upheaval, not prosperous reform.

At 75, the youngest of three brothers, he is only five years younger than Fidel and is inevitably seen as a transitional figure. Cubans fear that he will be weak and that corruption and turmoil will destroy the best remnants of Fidel’s socialist dream, while putting prosperity out of reach.

Two months ago, the party newspaper Granma (named after the boat on which Castro and his guerrillas arrived to fight the revolution) carried a long profile of Raúl, now defence chief. That was widely seen as the start of Fidel’s campaign to introduce his brother to Cubans as their next leader.

That campaign was never going to be easy. Even though Raúl has long been seen as the heir apparent, he is a shadowy figure compared with his loquacious and highly visible brother. Cubans know he is there but they do not know him well — and what they do know, they do not always like.

His authority, such as it is, stems not just from his position as head of the army, but from his record fighting at his brother’s side before the 1959 revolution which toppled the dictator Fulgencio Batista.

His reputation for ruthlessness stems from those early days. One of his first acts was to order the execution of 100 Batista military officers.

He has been married for more than 45 years to Vilma Espín, a chemical engineering graduate from the Massachusetts Institute of Technology, who had also fought beside him in the mountains. They have three daughters and a son. Some officials say that, contrary to an austere public image, he is warmer and “more human” than Fidel: singing, dancing, drinking and boasting fondly about grandchildren.

Many analysts say that he is much more pragmatic than his extravagantly idealistic brother, although he has been just as hardline towards the US. They credit Raúl with considerable managerial talent (easily eclipsing his erratic brother).

He has support from the 49,000-strong army which he built up, and has been famously intolerant of glossed-up reports from provincial ministers as the economy stuttered.

That is now his biggest dilemma. Fidel’s triumphs — strikingly high standards of healthcare and education, for a comparatively poor country — are deteriorating fast. The economy is sustained mainly by tourism and cash sent back from Miami exiles, although things are less bleak than in the early 1990s, when the collapse of the Soviet Union deprived Cuba of cheap oil and technology from its former protector.

In the face of this, Fidel has been fighting a battle that Tony Blair would recognise: to try to ensure that his ideals survive him. Raúl, at least, is expected to support that. As one US analyst put it: “He was a Marxist before his brother.”

In doing that, he may well back himself up with a troika of younger ministers: Pérez Roque, the 41-year-old Foreign Minister; Ricardo Alarcón, president of the National Assembly, 69; and Carlos Lage, the economics czar, 54.

But upholding those harsh ideals will not win him adoration, given the desperation of many Cubans for a better life.

The risk now is that Fidel’s death could bring turmoil: younger Cubans might stream out while Miami exiles poured in, claiming ownership of old villas and plantations.

Facing those threats, Raúl has all the disadvantages of being the younger brother of a superstar, without the advantage of actual youth.

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