Raul Castro turns 79 with eyes on future

By Jeff Franks

HAVANA (Reuters) - Cuban President Raul Castro turned 79 on Thursday, showing no signs of slowing down as he works to assure that Cuban communism survives beyond his generation.

His birthday was not mentioned in Cuba's state-run newspapers, possibly because the topic is a sensitive one for the country's aging leaders.

They have no obvious younger successors, but Castro, who replaced ailing older brother Fidel Castro in February 2008, appears to be in good health and in no mind to leave office anytime soon.

While opponents in the United States and elsewhere have long said the system installed after Cuba's 1959 revolution would die with the Castros, Raul Castro has made clear that he plans to keep Cuba communist long after he and his brother are gone.

"There are those in U.S. ruling circles who say they will wait for the disappearance of the revolution's historic generation, a sinister bet on the so-called 'biological factor,' or the death of Fidel and all of us," he said in speech to Cuba's National Assembly in August.

"Those who think like that are doomed to failure."

Cuban leaders are at work on "the ongoing upgrading of our economic model in order to set the foundations of the irreversibility of Cuban socialism," Castro told the Young Communist League in April.

The task is not easy because it is a fight against time and a powerful inertia that has settled over the Cuban system through its five decades of existence.