On all this, we're joined now by historian Douglas Brinkley.

He was a professor at Tulane University in New Orleans in 2005 when Katrina hit.

And he's the author of The Great Deluge, Hurricane Katrina, New Orleans, and the Mississippi Gulf Coast.

He's now a professor in humanities in the Department of History at Rice University.

Thank you for joining us.

Thank you for having me. We just heard the stories of people

who lived through Hurricane Katrina 20 years ago. Hundreds of thousands of people were displaced.

Many never returned. What is the legacy of that displacement? Well, it was a diaspora from a region.

I mean, it reminds me in history of the Dust Bowl of the 1930s when people fled Oklahoma,

New Mexico, Texas Panhandle for California, they just had to go somewhere else.

And like the Dust Bowl, Katrina is in about one date, August 29th, you know, it's really about years, decades that it's taking to

heal.

The effects of Katrina are still being felt in the Gulf South area.

Not everybody has been able to come back that wanted to, and a lot of neighborhoods haven't

been able to rebuild for various different reasons.

And Katrina, of course, exposed major failures in preparation and response from the levees to

evacuation planning to the federal government's slow reaction at the time.

What do you see as the biggest institutional breakdowns?

Well, the U.S. Army Corps of Engineers built Lego levees, and Louisiana hadn't supervised them properly for safety.

It's a city, you know, the mayor during Hurricane Katrina, Nagan, Mayor Nagan went to jail.

The current mayor of New Orleans is under corruption charges.

And as I speak, there's always been a sense of shoddiness that goes on in those

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