When the GOP lost a city
If Republicans want to be remembered as the party that destroyed New Orleans, they can go right ahead and do it. I'm sure the political damage they would face from losing an enitre city on their watch will be felt for years to come. Republicans can't afford not to rebuild the place. Not in the politics of the country today.
By the way, there are any number of reasons for rebuilding. And if Bish and co. need some pointers on how to protect the city perhaps they could ask these guys for help.