Re: I'd like to qualify this statement by saying I do NOT know much about Katrina, but my
New Orleans wasn't evac'd by force (as in, the national guard coming in with the sherrifs and loading people into trucks) because the storm actually MISSED the city. The eastern eye wall, which is the strongest part of any hurricane, passed to the east of the city leaving New Orleans to face the weak western side of the storm. The brunt of the storm hit the gulf coast of Mississippi including the cities of Gulfport and Biloxi, which were almost completely eradicated. I've lived in both areas both before and after the storm, and there's no comparison in the damage between New Orleans and the Gulf Coast.
What did all the damage in New Orleans was the failure of several levees / stormwalls, which provide protection along the canal systems used in industrial shipping in the city. At least one levee breach was caused by a cargo barge that broke free of it's moorings and slammed into and through a floodwall, causing extensive flooding.
Had the levees and floodwalls performed as intended, New Orleans would have fared vastly better. Nothing would have saved the Gulf Coast.