Why do the USA have a naval base in Cuba?

Location of the U.S. Guantánamo Bay Naval Base

Source: http://en.wikipedia.org/wiki/File:Guantanamo_Bay_map.png

The consequences of the Spanish-American War are still evident in some contemporary facts: 

- Puerto Rico continues to be under USA control. It´s an associated free State, but the USA decide on many aspects in Puerto Rico, although its citizens can´t vote in the USA presidential elections. 

- Although the USA and Cuba don´t have official relations since the Cuban Revolution in 1959, the USA still have a naval base in Cuba: Guantánamo. This is the explanation: after the signature of the Peace of Paris in December 1898, the USA army occupied Cuba. In 1902 Cuba became an independent republic and the Parliament wrote a Constitution. But in 1903 the USA government obliged the Cubans to add an amendment to the Constitution. This is was the Platt Amendment, which gave the USA the right to intervene in Cuba when they considered they had to do it. Also in 1903 the Cuban-American Treaty was signed. This treaty included the creation of a naval base in the southeast of the island. That was the origin of Guantánamo Bay Naval Base, the oldest USA base overseas. President Theodor Roosevelt signed a permanent lease of the base and a yearly rent was established (2,000 gold coins).

When the Cuban Revolution took place in 1959 and Fidel Castro reached power, the Cuban government denounced the lease treaty as illegal and refused to cash the cheques the USA government send every year. 

In 2002 Guantánamo Bay Naval Base became famous worldwide, because the USA government created a detention camp (GITMO) for the alleged terrorists and enemies captured in the wars in Afghanistan and Iraq. Several human rights´ organizations have denounced the detention conditions of prisoners, the use of torture and the legal limbo of Guantánamo. President Obama promised to close the detention camp, but he hasn´t done it yet. 

Source: http://www.indymedia.org.uk/en/2012/01/491112.html

Here you have some more information about Guantánamo Bay Base: 

http://www.historyofcuba.com/history/funfacts/guantan.htm 

Guantánamo Bay Detention Camp:

http://www.wisegeek.com/what-is-guantnamo-bay-detention-camp.htm

http://news.bbc.co.uk/2/hi/americas/4720962.stm 

Inside Guantánamo. Photo report: 

http://www.washingtonpost.com/world/inside-guantanamo/2011/04/24/AFtqQJdE_gallery.html#photo=1