The answer to a lot of these questions is that it's all a simple matter of logistics. For one thing, the storm destroyed all of the roads into NO except for the highway heading west. For another, the transportation (trucks, busses, etc.) has to be obtained...and this is a matter of getting drivers and mechanics and other support people...and oh yeah, gas. Since all of the filling stations in southern Louisiana and Mississippi are either destroyed or under water, they will also need tanker trucks. For yet another thing, they can't take people to an evacuation site until that place is prepared to accept them. And the regular military and the Guard can't arrive immediately. They need to have some time to get ready (the Guard members all have civilian jobs that they generally can't abandon on a moment's notice), get to wherever their depot is, get loaded up...and they also have to get around the city to that single road in. Somebody suggested aircraft carriers? Well, they move along at about 30 miles an hour...not exactly fast responders.

As someone said, lets wait a bit until we start pointing fingers. And the same goes for the mayor of New Orleans and for Mr. Bush. We all know what Harry Truman's desk sign said...I guess his says "The Buck Stops There".