Yes it was, but the map illustrates where those slaves went, and gives you an idea of how big each slave industry was. The Carribbean slave business was bigger than the Southern state slave business.
The possibility of the South expanding there would have required them to compete with the existing and much larger slave plantations already in place.
The possibility of the South expanding there would have required them to compete with the existing and much larger slave plantations already in place.
I repeat: at the time of the Civil War, slavery had been abolished except in Brazil and in Spain's remaining colonies (Cuba and Puerto Rico), and (until 1863) the Dutch colonies. The British, French and Danes had already abolished slavery in their colonies, as had the Spanish-speaking Republics.
Southern desires to expand into the Caribbean are well documented. It was felt that a larger area under Confederate control would make slavery more secure. Moreover, if you really wanted to make Charleston or New Orleans the successor to New York, expanding the empire of slavery would be a good strategy. So your own cockamamie theory condemns you.
Expansion into Cuba or Puerto Rico would have the effect of consolidating the slave area, and preventing abolition. Expansion into Mexico or Central America would be expanding the slave area, bringing slaves and slave owners from the US into the new acquisitions. As for Haiti and the smaller Caribbean islands, they would have been more trouble to the Confederates than they would have been worth.