The federal government had no real jurisdiction, time or ability to bring folks in and use these to move people out of New Orleans pre-Katrina.
Local natural disasters can only be dealt with at the local level in early stages, and/or prior to predicted disasters with short notice. The corruption of redirecting federal funds earmarked for flood protection improvements by New Orleans politicians to other places (or their own pockets) was the real crime in this disaster. ...and the victims reelected them to office!