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Rafael is about to finish his degree at Havana University, but his mind is elsewhere. The finance and economics he is learning are "what they use here in Cuba," he explains.

He is among the many young Cubans who respond to their crimped prospects not by agitating against the system but by plotting to escape it. Rafael (not his real name) does not oppose Cuba's communist regime, nor does he take much interest in it. So he is unexcited by a power shift that will make headlines around the world.

On Thursday, Raúl Castro plans to step down as president, bringing to an end nearly 60 years of rule by the family that led the country's revolution. Rafael thinks it is time for Castro to go, but says "it doesn't matter to me."

It will matter to most of Cuba's 11 million people, who have no easy way off the island. In a country where transfers of power are rare, the one about to occur is momentous.

Castro, 86, is expected to hand power to the "first" vice president, Miguel Díaz-Canel. He had not been born when Raúl's brother, Fidel Castro, toppled the American-backed dictatorship of Fulgencio Batista in 1959.

The post-revolutionary generation will bring a change in style and raise Cubans' expectations of their government. It is unclear whether new leaders will meet them.

Díaz-Canel, an engineer by training, has acquired a reputation for modesty during his quiet three-decade ascent through government and the Communist Party. As a leader in his home province of Villa Clara in central Cuba, he rode around on a bicycle rather than in an official car. At the (one-party) parliamentary elections last month, he queued up with other voters and chatted to the press.

Díaz-Canel has sometimes seemed more liberal than other apparatchiks. He backed gay rights before it was fashionable. In 2013 he calmed a furor caused by the censorship of some student bloggers who were critical of the government. He met the students in front of the press and said that in the internet age "banning something is almost a delusion."

His elevation to the presidency will be part of a broader generational change. Several octogenarian conservatives, such as José Ramón Machado Ventura and Ramiro Valdés, will probably leave the council of state, a body with lawmaking powers. Díaz-Canel is expected to replace government ministers with his own people.

But substantive change, if it happens, will not be abrupt. Although la generación histórica will no longer run the government day to day, it will still be influential. Until 2021, Castro is expected to remain head of the Politburo, which controls the Communist Party and thus the overall direction of policy. Ventura will remain second-in-command. Díaz-Canel will be only the third most powerful member.

He may not be the reformer some Cubans are hoping for. In a speech to a private Communist Party meeting, a video of which was leaked last August, he vowed to shut down critical media and boasted of his efforts to throttle civil society. He called the loosening of the U.S. embargo on Cuba by President Barack Obama starting in 2015 an attempt to destroy the revolution. Díaz-Canel was shoring up his flank to ensure his promotion to the presidency, said William LeoGrande of American University in Washington, D.C.

Others see the speech as evidence that Díaz-Canel will be no friendlier to critics of the regime or to the United States than the Castros were. No one expects him to allow opposition parties or a free press.

A more plausible hope is that Díaz-Canel will follow the example of communist parties in China and Vietnam, which opened up markets and allowed citizens to enrich themselves while maintaining political control.

But even this may not happen. Attractive as the prospect might sound, Cuban politicians fear it would turn their country into a sweatshop making cheap goods for rich Americans. Socialism, political scientists point out, was less entrenched in Vietnam than it is in Cuba.

But Díaz-Canel cannot avoid economic reform of some kind. The economy is in terrible shape and getting worse. Venezuela, whose like-minded regime has provided aid in the form of subsidized oil, is in economic crisis and sending less of it. The fall in trade between the countries, from $8.5 billion in 2012 to $2.2 billion in 2016, caused Cuba's first recession since the collapse of the Soviet Union, its benefactor during the Cold War. Cuba's budget deficit reached 12 percent of GDP last year, hit hard by the cleanup after Hurricane Irma struck last September.

State-controlled farms and factories are incapable of producing the goods Cubans demand, and a lack of foreign exchange makes it hard to pay for imports. Shortages, of everything from tampons to salt and sometimes electricity, are a plague.

This is straining a 60-year-old covenant, under which the regime provides security, free public services and a tolerable standard of living in return for its people's quiescence.