What has always irritated me about the Katrina aftermath is the beating the U.S. government took over it. Yes, they made some colossal mistakes, but the brunt of the blame has to fall on the lack of leadership and mistakes by the city and state governments.
Alabama has a coastline, and the year before, took a direct hit from Hurricane Ivan, which did tremendous damage, although obviously, not like Katrina.
The mayor of Mobile ordered mandatory evacuations 48 hours before landfall. Alabama Gov. Bob Riley ordered contraflow on the main interstate leading north, away from the coast, 72 hours before landfall. That meant that all the traffic for some 150 miles was all moving north in both lanes, which facilitated people being able to get out.
The mayor of New Orleans ordered mandatory evacuations only 20 hours before landfall, for a city three times the size of Mobile, when the warnings had been out for New Orleans for two days. The governor of Louisiana never ordered contraflow on I-10, or I-59, the two major interstate highways out of town.
Also, the emergency management officials had abandoned a plan put in place by a retired EMA director to commandeer all the city's buses and school buses to get the Ninth Ward evacuated by no less than 48 hours before landfall.
While the Army Corps of Engineers perhaps did not maintain the levees as well as they should have, the city of New Orleans signed its own death warrant when developers convinced city leaders to go along with draining the salt marshes and putting shopping centers on them. The salt marshes were a natural means of defense for the city, since they could absorb huge amounts of flood water. That line of defense was gone, though.
The government of New Orleans had convinced itself that, since the city survived hurricanes Audrey and Betsy, that it could survive anything. Only those hurricanes hit the city in the 1950s, when the population was much smaller and the salt marshes were still intact.
My city hosted many Katrina refugees, and the national media and the pundits never talked to them. They could tell stories about how that "laissez les bon temps roulez" attitude nearly destroyed the city. My cousin's in-laws also lived in New Orleans at the time. Her mother-in-law (a nurse) stayed for five surreal days in the Tuoro Infirmary, helping people, and she can tell some stories about the city's ineffective preparation and response to the disaster.
The upshot of it is New Orleans got caught with its pants down. The sad part is the most vulnerable citizens were the ones who paid the highest price.