http://www.monthlyreview.org/0302editr.htm

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According to the Defense Department’s Base Structure Report, 2001, the United States currently has overseas military installations in thirty-eight countries and separate territories. If military bases in U.S. territories/possessions outside the fifty states and the District of Columbia are added, it rises to forty-four. This number is extremely conservative, however, since it does not include important strategic forward bases, even some of those in which the United States maintains substantial numbers of troops, such as Saudi Arabia, Kosovo, and Bosnia. Nor does it include some of the most recently acquired U.S. bases. Through Plan Colombia—aimed principally at guerrilla forces in Colombia but also against the less than servile government of Venezuela and the massive popular movement opposing neoliberalism in Ecuador—the United States is now in the process of expanding its base presence in the Latin American and Caribbean region. Puerto Rico has replaced Panama as the hub for the region. Meanwhile the United States has been establishing four new military bases in Manta, Ecuador; Aruba; Curaçao; and Comalapa, El Salvador—all characterized as forward operating locations (FOLs). Since September 11, the United States has set up military bases housing sixty thousand troops in Afghanistan, Pakistan, Kyrgyzstan, Uzbekistan, and Tajikistan, along with Kuwait, Qatar, Turkey, and Bulgaria. Also crucial in the operation is the major U.S. naval base at Diego Garcia in the Indian Ocean. All told, the United States now has overseas military bases in almost sixty countries and separate territories

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Map of current bases of the U.S. military (worldwide).

http://www.monthlyreview.org/0302map1.pdf