The history is what it is. Federal troops sat in Charleston harbor for a long time too. The question was, what if Castro told them to get out of GTMO tomorrow.
What would you do Mr. Carter?
If Fidel Castro (or whoever is about to replace him as he's going to die within a year) said for us to get out of Cuba I would get out of Cuba same as I would expect them to get out of the U.S. were it vice versa.
Ahem: Guantanamo Bay is leased from Cuba and is nominally subject to Cuban sovereignty.
http://en.wikipedia.org/wiki/Camp_X-Ray
No wonder you associate with Lincoln so much. You're as jingoistic and dictatorial as he was.