There's a narrative running with this story I don't buy: the barriers installed on the streets weren't up like they should have been. And, IF they were?
Recently I was sitting outside of the Ashley Towers at MUSC. I noticed some of the concrete barriers they had installed at ground level (contains main lobby, women's specialty care, and their "testing" wing for blood work, etc.) I asked about the barriers in front of the women's area and was told by the asst. head of security it was to prevent vehicles from crashing the building. (Three different projects over the last quarter of a century just adding a pole here, a pole there, etc.)
He couldn't answer one question. I pointed out there were barriers in front of that department for the women, but nothing in front of the main lobby entrance. I could literally drive a box truck in the front entrance, turn left and drive a box truck down the hallway. (That front entrance to the lobby is all glass. I literally watched people walk into the glass a few times a day while there.)
I was there a few nights and spoke with him every time we saw each other. As we looked around it was evident: there was little to no planning involved. It was all eye candy that serves a little purpose. "The world is a stage" represented.
Now, with New Orleans? Yes, the gates were down. Yes, there was a police vehicle blocking the middle of the road. And also yes...all he had to do was drive up the sidewalk, take a turn, and he could have driven a truck down Canal ... oh, wait.