If some country wants to become part of the United States of America...
I say let them. So long as it does not waterdown the already established Constitution and laws of the United States...
Of course political elements in Washington will do everything they can to maintain the Status Quo...Or to play-up any changes to their side of the aisle's political advantage. For example, the Democrats would love Quebec as the 51st State with its leftest Socialist leanings. The Republicans would love Alberta as the 51st State with it's rugged individualist and agricultural leanings.
Post-Catro Cuba would be good if it voted to go that way...Which it never will...
Scott