everybody can read and see that this is exactly what you have been doing
castro is still in power for the same reason that saddam remained in power during the sanction years. they were able to consolidate their grip during sanction/embargo years because lack of goods allowed them to control who got what. instead of pushing these countries to be open to outside influence via business, travel, media and whatnot, and eventually develop democratic constituencies, we gave them further opportunity to crack down on all forms of opposition. cuba makes all of this abundantly clear.
So how do you have free trade with a country and not support it?