BBC NEWS | World | Americas | US to tighten Cuba sanctions

What would have happened if the US had left Cuba alone rather than imposing sanctions 40 years ago? Castro says (in the Oliver Stone documentary) that he would never have had to become so heavily dependent on the Soviet Union for help. There might have been give or take. Maybe Cuba would have ended up like other Central American republics : Leftist governments, CIA backed guerrillas, by now it could be like Guatemala or Nicaragua. (Maybe it's better off as it is.)

Or maybe, after the soviet collapse it might have ended like Eastern European countries, keen to try something new. Why didn't it? The Romanians managed to get Caucescu. Why didn't the Cubans rise up and shoot Castro in 89?

Because he's popular. Despite the repression. Despite the lack of freedom. Despite the fact that many Cubans dream of going to US and getting rich. A lot of them think they're better off under him than they were before. Or than they might be if they end up like Guatemala and Nicaragua.

Could Cuba have ended up like Vietnam? Or another island with a high investment in education and an authoritarian ruler : Singapore?