"I don't see any major changes that we've done in this country," Nagin said on NBC's "Today" show today.
"I agree with the mayor," added Brown. "I think the systemic failures that we have there have not truly been addressed."
Americans are of the same mind. A new poll released by the Pew Research Center this week found that 57 percent of respondents, including a majority of Republicans, Democrats and independents, also thought the country's preparations for a natural disaster remained inadequate.
And yet, neither Brown nor Nagin -- who were often at loggerheads throughout the widely criticized response effort -- admitted to mishandling things back then.
"We thought we had done a pretty good job on evacuation," said Nagin. He noted that for previous storms, 60 to 70 percent of the city had been evacuated. For Katrina, between 80 to 85 percent left. Some stayed because they didn't have the means to leave and also, Nagin said, because New Orleans' culture is "one of stay and ride it out."
Brown blamed the disconnect between Washington's upbeat statements and the crisis on the ground on the capital's political culture. "There's this mentality in Washington that says you put the best face on everything," he said.
He said he never lied to the American public. "Nothing was inaccurate. It was factually correct in what we were telling people what was going on. But we never put it in context about we're doing all of these things, but it's not enough or it's not working."
Watch the full interview below or at MSNBC.