Final answer:
The United States established a naval base at Guantánamo Bay due to the Platt Amendment, which was part of the terms for Cuba's independence from Spain. The base has been used for various military purposes and more recently as a detention center for terrorism suspects.
Step-by-step explanation:
The United States established a naval base at Guantánamo Bay. This was a result of the Platt Amendment, which was introduced after the Spanish-American War when Cuba was seeking independence from Spain.
The Amendment put various conditions on this independence, one of which was that Cuba had to grant the U.S. the right to establish a naval base on their territory.
This base has been a source of contention between Cuba and the United States and has evolved in its use over time, especially known in recent history for the Guantánamo Bay detention center established by the Bush administration in 2002 for the detention of terrorism suspects.
The purpose of establishing the base was strategic; it allowed the U.S. to project its naval power in the Caribbean and to protect the newly acquired territory of Puerto Rico. Over time, the base has been used for various operations, including the detention of enemy combatants, which was a significant policy decision during the Bush administration and addressed by President Obama during his term.