In the 70's during the Manley years, Cuba sent lots of doctors, nurses and medical supplies to JA. Medical clinics were built in areas that previously had none.
The big bad US told JA that if they wanted to stay in its good graces, it had to kick out the Cubans. So away went the doctors and nurses, and the medical clinics soon were without equipment and supplies. did the US step in and help out? Nope. They just didn't want Cuba to be there.
The US's policy regarding Cuba is absurd. We do business with many communists/socialists/dictators, just not little Cuba.
I think that the US policy only makes Castro more popular, not less.
As usual, this is just my opinion...