Do you think New Orleans is going to do it again? How many states have passed laws against that since the Katrina/Nagin debacle? It is now less likely than it ever has been.
Yes, I do think NO would do it again and I completely believe the officers ordered to do so would follow their orders. Then the NRA and SAF would have to go to court to get an injunction to stop it.
There already was a law against what they did. It is called the Constitution of the State of Louisiana. The Judge in the case found the police guilty of violating THE LAW in confiscating firearms, ordered it stopped and the guns returned (still not done!).
So the NO LEOs broke the law once. There is now another law. Why should you believe they will obey it too?
Laws mean nothing when the gov't chooses to ignore them.