[Update...the AP numbers seem to be erroneous. There is less here than meets the eye. See below.]
To answer the commenter's question in my original post of "who dispatched the National Guard]?" I began Googling. Now I doubt the 10,000 number in the AP chronology story I quoted.
Jeb Bush
calls up 1,000 in FL on August the 26th.
the National Guard news archive has no other call-ups beyond that 1,000 in their press releases until the 29th.
This press release from the 29th seems to refer to way less than 10,000 callups.
"The Louisiana National Guard had called almost 3,500 of its members to state active duty as of 7 a.m."
"In Mississippi, nearly 900 Army and Air Guard members were on active duty, with as many as 600 more expected to join them by the day's end..."
"An estimated 160 Alabama National Guardsmen were on duty in the southern part of the state..."
Other Guard numbers in the release refer to "available" and "stand-by" personnel, 9,000 in Alabama and 9,000 in Arkansas.
Then on the 31st, this release states: "The Alabama National Guard will send an additional 1,400 and Army and Air National Guardsmen to Mississippi on Thursday." Later in the release it says "by Wednesday afternoon, 10,000 Guardsmen will be on duty in Louisiana, Mississippi, Alabama, and Florida. By Thursday, there will be 20,000."
[This original post, relying on the AP numbers, appears reach a wrong conclusion, and I withdraw it.]
Something I didn't notice before. According to this AP chronology, 10,000 National Guard troops were dispatched to help the day after Katrina crossed the state of Florida as a Category 1 hurricane. On Saturday August 27th when Katrina became a Category 5, Bush declared a state of emergency, which put FEMA in charge of coordinating the emergency response. On Sunday the 29th, a disaster was declared for Louisiana.