LouderVol, your history on Katrina is way off. Here are some facts:
1. The Governors of Louisiana, Missisissippi and Alabama all called out their National Guard units and had them positioned to support disaster relief operations prior to the Hurricane hitting land.
2. The Defense Coordinating Officers and staffs were activated and established in their operations centers prior to land fall.
3. There were thousands of pounds of disaster relief equipment and supplies positioned outside of the expected impact area to be moved in as soon as the danger passed.
4. Bush did declare a national emergency and did order FEMA to provide disaster relief based on the needs of the states.
The local, state and federal agencies involved were in fact in place to support the expected disaster and its aftermath. However, that wasn't the disaster they got. Instead they got a disaster that was exponentially greater then they expected. Not only was it larger than anticipated, but the storm stalled over the region far longer than anyone expected. That resulted in the following:
1. The breaching of the levies in New Orleans. They planned on the levies holding which would allow interior mobility to get buses and trucks around the city and to the Super Dome to facilitate the evacuation.
2. The flooding of the 9th Ward included the flooding of the National Guard Headquarters that was coordinating disaster relief. It was difficult for the National Guard to provide relief when they found themselves under water.
3. The extended storm and flooding disrupted the command and control within the city, especially the Mayor's office. There is also a huge issue that the Mayor of NO did not participate in any of the disaster relief training and didn't know what he was supposed to do. That is why you saw him on the news calling for support when he should have been on the phone or in his emergency operations center helping lead the relief efforts. It is also why one of the first flights in included a fire breathing Army LTG who Bush ordered to personally get things organized. (There was some discussion at the time that may have been illegal, but they did it anyway).
4. All the roads into the disaster area, especially around Mobile, were blocked, significantly delaying the arrival of the National Guard.
5. Thousands of people who should have evacuated prior to landfall decided to ride out the storm. Many of them made it to the Super Dome, but were stuck there when the buses couldn't get to them (either because of the flooding or incompetence of the Mayor). Many were spread at random throughout the city and no one had any clue who or how many there were. And, even though they decided to stay put, they then demanded rescue when the flooding started.
There were other huge mistakes that we learned lessons from (that were successfully implemented during later storms such as Hurricane Sandy):
1. Coordination of evacuations that cross multiple state borders and the need to change interstates highways and state highways to all lanes going outbound.
2. A new perspective on the way you organize shelters. In almost all other disasters the individuals who went into relief shelters pitched in to help run the shelter as much as they were able. People were expected to help set up cots, serve food and so forth. No one expected the level of lawlessness, including murder, rapes, abuse and theft, that occured in the Super Dome. No one expected the people would simply sit and wait for someone to come along and tell them what to do. We now know that a percentage of our population will need a huge amount of supervision and guidance in a disaster that they didn't need previously and organize accordingly.
3. New rules on ordering evacuations and how to inform people what will happen if they decide to stay put.
4. New standards for emergency operations centers, including a review of their locations to make sure they don't get inundated by the disaster.
5. New rules for the evacuation of hospitals, retirement homes and any one else with mobility impaired people, to ensure the horrors that happened in N.O. aren't repeated.
In the end, you can shout "Bush should have _________" all day long. But the fact is, he did what he was supposed to do, as did the various federal and state agencies. But it was a 1000 year storm that caused widespread and unexpected damages.
Many will say he should have landed in NO and walked the ground for himself. Having been on the ground when a POTUS comes for a visit, I would disagree. The entourage the POTUS brings would have been a circus in the middle of all that chaos. He would have taken resources (time, attention, security etc) away from the relief operations. So I think flying over and seeing the disaster was appropriate. I also think the plan was executed as best as possible given the circumstances.
(PS if you need to know how I might know some of this, I was part of the disaster relief for the SF earthquake in 89, Hurricane Andrew (93?) and was assigned to the Defense Coordinating Office in Hawaii at the time of Katrina. We stood up and tracked the situation because we expected to be activated and flown in to assist but were stood down before deploying).