Hurricane Katrina revealed much that is wrong with political government. Government was responsible for disaster preparation and response. Government failed. Not only did it fail, government hindered private charity. The politicians and bureaucrats had other priorities. This is not new. It's been going on for generations. It's the nature of political government.
Now we are expected to trust government to rebuild New Orleans. The federal government wants to spend over $100,000 for every man, woman and child that was living in New Orleans. By the time it's paid off the expense would probably be more than $1,000 for every man, woman and child living in the US.
In contrast, I suggest that the best way to rebuild New Orleans would be to make it a tax-free (and government appropriation-free) zone. Business investment dollars would flock to New Orleans. Property that is now near worthless would become very valuable. The government would actually make money by selling government owned real estate, including the levees. Businesses and their insurance companies would have the means and the will to make sure that a privately owned and insured flood and hurricane mitigation infrastructure would protect them. New Orleans and Louisiana could be more prosperous and more secure than ever. New Orleans could become an economic giant.
This would be good for the people of New Orleans, good for the people of Louisiana, and good for the people of the U.S. It would be good for everybody except the politicians and bureaucrats, who would be embarrassed by their relative failure, which is why it will probably never happen.