Well, just think rationally about it. Much of New Orleans will be unlivable for many months, if not a year or more. The people who have been moved will gain resettlement assistance, and the quality will be relatively high because of public relations. For that matter, if we wanna be crude, public assistance is much superior in these other states than in New Orleans. People who want them will find jobs, and in either case they will settle down.
As New Orleans gets rebuilt, there will surely be economic incentives to pull people in. These will be skilled people by and large, not the sort that populate slums. The demographic profile of the city will change totally. The construction activity will by and large pull in the usual typology, and that will be heavily Latino. A lot of immigrants will be attracted to the opportunities, and they will be heavily Latino. Moreover, there is likely to be an influx of whites comparable to what always happens in gentrifying urban neighborhoods, since in a sense that's what's gonna happen: radical gentrification.
Explosive or not, that's just how it's likely to play itself out.
We shall see how the clash between PC politics and economics plays out. I hope that you are right. But obviously, Dems in Louisiana are upset about the out of state roots thing.