Hurricane damage estimates don't differentiate between whether or not flooding was caused by levee failure or by flooding. If you think New Orleans was better off after Katrina hit you're insane. The population of the city dropped by about 30%, that's the largest drop of any US metro area in the history of the country if I'm not mistaken. It was in every way, an unmitigated catastrophe.
I am aware of no credible source that believes the oil drilling ban has caused more damage to Louisiana than Katrina. It's insanity.
I umm sorta kinda live and work here. Yes the population dropped, it was mostly poor people that the city did a horrible job helping provide opportunity to and who are likely much better off were they are now. That would be why they didn't come back. The large rise in housing costs after Katrina might have had just a bit to do with it too. We also have entire areas (New Orleans East to be specific) that probably shouldn't have been allowed to rebuild in which absurdly few services exist (hospitals, schools, etc..) due to it now being extremely sparsely populated.
disclaimer: I say "shouldn't have been allowed" I really mean people told that the area will be the last to be rebuilt and only when the population in the area is growing at a rate to sustain it, people should be free to rebuild on their own property if they so wish but they deserve the truth before they do.
As far as "credible source", how about the actual residents actually being affected by the moratorium. It isn't the
spill that is ruining these people, it is the moratorium. The very same people BTW who had to actually rebuild after Katrina. For the record, I actually lived through both and almost everyone I know was affected by both in some way or another. Katrina was a kick in the nuts followed by prosperity, the moratorium was a kick in the nuts after a kick in the nuts followed by poverty. See the difference?
I'll be making a trip to Grand Isle this weekend, if you like I can ride through Port Fourchon and knock on the doors of some businesses (the ones still open) and ask them for you. Or are they not "credible" enough for you?