a question about cuba

[boracay]

ok, americans can't visit cuba. why is this so good?
is it fear cuba would get millions from americans (i guess the fear americans would get infected by communistic ideas couldn't stand once they see it) or is it something else?

i believe tourists bring ideas/demands/desires/needs/etc from the other world and when people would realize that it might speed up the process of decay of their system. am i wrong here?

although, their regime would have much more problems and castro would probably allow visits in their resorts only IMO.

i might be wrong, but it seems to me this is good for US administration, somehow good for castro, somehow bad for americans and very bad for cubans.