Visit.
Maybe set up some cafes in Havana.
Advise historical preservationists on how to gentrify all the run-down but still lovely (in their moth-eaten way) architectural relics.
Picket Guantanamo.
Organize the agricultural workers into unions so that plantation owners will never again develop an economic structure in which workers were so close to serfdom that the likes of Fidel Castro could become a popular nationalist hero simply by opposing the landowners and their political associates.
Perhaps some of them will even buy some cigars...