The biggest concentration is at Wright-Patterson Air Force Base near Dayton, headquarters of the Air Force Materiel Command and the Air Force Research Lab.

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Rumsfeld was returning from a visit to Central Command headquarters at MacDill Air Force Base in Tampa, Florida, when he commented to reporters.

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In Tampa, Mrs Kelley has served as an unpaid "social liaison", helping to organise gatherings at MacDill Air Force Base, which is the home of US Central Command.

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There are 46, 000 troops in Special Operations Command, which is based at MacDill Air Force Base in Florida.

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Wild said her son always wanted to go into the military, like his father, who is a command chief in the Air Force Reserve at Dover Air Force Base in Delaware.

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President Bush, in Florida when the attacks occurred, canceled plans to return to Washington and addressed the nation from Barksdale Air Force Base in Louisiana and later traveled to the U.S. Strategic Air Command headquarters in Nebraska.

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Liang is scheduled to visit the U.S. Southern Command in Florida, and tour Camp Lejeune and Seymour Johnson Air Force Base in North Carolina as well as the U.S. Military Academy in West Point, N.

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