>>New Orleans obviously needs help way beyond anything that's ever been needed before after a hurricane in the U.S.
>
>I think if New Orleans was a normal large town, small city that it would just be abandoned, but because of its special status as a cultural place, it will eventually be rebuilt.
>
>Take a look at this hurricane from 1900, it also list an even bigger one that happening during the American Revolution.
>http://en.wikipedia.org/wiki/Galveston_Hurricane

I didn't read the reference.
But times surely are way different now. There is a depenence on both electricity and automobiles/busses, neither of which applied in those.
There is dependence on running water and sewage systems, which Galveston may have had some of but nothing like today.
People back then were largely self-sufficient whereas today virtually no one is.
Finally, just the sizes of the populations involved make this one hugely different.
I can't see any legitimacy in comparing either of the ones you cite, save possibly for counts of killed.