Even if Guantanamo prison closes US will not return Guantanamo to Cuba
In a recent speech, U.S. Secretary of Defense Ash Carter said the U.S. intends to keep Guantanamo Bay Naval Base in Cuba whether or not the prison closes down.
Carter said it "would be nice" if the U.S. can close the detention centre at Guantanamo and move the remaining detainees somewhere within the U.S., but even if the prison is closed the U.S. will keep the base in spite of objections by the Cubans.
According to Wikipedia Guantanamo Bay Naval Base:
The lease is in perpetuity and can only be cancelled by the agreement of both parties. The Cuban government has protested consistently against the U.S. presence at Guantanamo and claims it is illegal under international law and was originally imposed upon Cuba by force. In 2013 at the UN Human Rights Council Cuba demanded that the U.S. return the base and other "usurped territory" it took when the U.S. invaded Cuba during the Spanish-American war of 1898.
Guantanamo Bay is the oldest overseas US naval base, being occupied for over 110 years. It has been used as a detention center since 2002. Even with the recent establishment of diplomatic relations between the U.S. and Cuba, the U.S. has made no promises to return the base but has promised only to "discuss" the issue. Perhaps the U.S. might at the very least offer a more reasonable payment for the lease. The Cubans have refused to accept the checks that the U.S. faithfully sends each year.
Carter said that Guantanamo Bay base was "strategically located" : “We’ve been operating for a long time and that’s going to stay important. I don’t see us changing that.” Although Cuba insists that for complete normalization of U.S.-Cuba relations, the U.S. would need to return the base to Cuba, the Obama administration insists that currently the matter is not even being discussed. The return of the base to Cuba seems even more unlikely than the closing of the prison complex in the near future.
... is located on 45 square miles (120 km2) of land and water at Guantánamo Bay, Cuba, which the United States leased for use as a coaling and naval station in the Cuban–American Treaty of 1903 (for $2,000 until 1934, for $4,085 since 1938 until now).