The temporary rise of Raul Castro to the top of Cuba's government may test the succession mechanism on the island, but may not foreshadow a political transition, which will be long and limited, experts said.
Cuba watchers describe Raul, Fidel's brother and defense minister who was temporarily elevated to Cuba's presidency late on Monday, as a pragmatic, efficient and extremely well organized man with a reputation for toughness.
All this gives the younger Castro, at 75, all the qualifications for leading the government in a crisis situation, particularly now that Fidel Castro, 79, announced his health problems of uncertain gravity.
In addition, Raul controls the armed forces, which in effect manage the Cuban economy.
However, observers also point out that Raul does not have either the charisma of his brother or the eloquence as Cuba's political system remains tailored to Fidel.
He may have created a split in the armed forces by prosecuting general Arnaldo Ochoa, a hero of the Cuban Revolution who was executed for corruption and drug trafficking in 1989.
His arrest was announced by Raul, who spoke on the matter for two hours during a military celebration.
"Surely, he will be handicapped, severely at first, because he will in no way resemble Fidel in power and because popular anxieties will be high. He will have little room for error," Brian Latell, a former CIA expert on Cuba, wrote in a recent article.
"Raul is a plodding, maladroit public speaker, and has never been able to sway a crowd or inspire an audience with his own uplifting visions," Latell pointed out.
Nelson Cunningham, a former adviser to president Bill Clinton on Latin America, said Raul will be a transitional leader in any event because of his advanced age.
"I think we have to view Raul as a transitional figure, even if Fidel does step down permanently," Cunningham opined. "Even if Raul does become the leader of Cuba, he's 75 years old. He will not have many years left. Inevitably, that would begin a period of real transition."
Jaime Suchlicki, a University of Miami academic who last February took part in an exercise that examined various scenarios in post-Castro Cuba, predicted that Cuba "will not undergo radical change" at this stage but rather "a long and difficult transition."
"I was the only one here who said after the collapse of communism in the Soviet Union, `Please buy the suitcases, but don't pack them just yet,'" Suchlicki recalled.
He said the same logic would apply to Cuba.
The academic said that Raul, sometimes described as a reformer in the Chinese or Vietnamese mold, "could introduce some reforms, but they would be small and take a long time to implement."
Local observers believe the Ochoa case could make it difficult for Raul to hold onto power for a long time. However, it remains unclear how deep the split within the military is.
The army has since been purged, and General Abelardo Colome, a Raul loyalist, now heads the general staff.
Moreover, political and ideological work within the military is supervised by the Communist Party.