"Until 2001, the Alamo City was home to five installations. Today there are four: three Air Force bases and the Army's Fort Sam Houston. Add two major military hospitals, two spy agencies, and a slew of smaller organizations that play critical roles in the war on terrorism. All this makes the area a magnet for military retirees and their dependents, with an estimated 50,000 to 70,000 retirees in greater Bexar County alone.
...[C]ity leaders were nervous last summer as the Defense Base Closure and Realignment Commission scrutinized installations around the nation. In the end, the commission ordered the closure of the Air Force's Brooks City-Base, although some of its organizations will remain in San Antonio. All 21 bases on the BRAC Commission list must close within six years."