About 15 km away from the city lies the Guantánamo Bay, a superior natural harbor which has been utilized by the United States since 1898, when it was captured from Spain in the Battle of Guantánamo Bay. In 1903 Cuba leased it to the U.S. as it had committed to in the Cuban–American Treaty of Relations, and remains the site of a US Navy base, as well as the Guantanamo Bay detention camp.
As mentioned in article 2,
the High Contracting Parties shall respect each other′s territorial integrity and reaffirm the inviolability of the borders existing between them
Russia invaded Crimea back when British red coats were stationed in New York City. The Russian military has been there ever since.
When did the US invade the Guantanamo section of Cuba?