Worst-case scenario

Road blocks out of action when attack took place

- Ramon Antonio Vargas

Aaron Miller, the former homeland security director of New Orleans, was terrified after a gunman drove a truck into a crowd celebrating Bastille Day in the French coastal city of Nice in 2016, killing 86 people and wounding many more in a terrorist attack claimed by Islamic State.

Similar attacks in Berlin, London, New York and Barcelona also put him on edge as he thought about the safety of his city. "We just said ... it's just too risky right now" not to fortify New Orleans' historic Bourbon Street, known for its bars and clubs, he said. "God forbid somebody does this [here]."

By the end of 2017, Miller had overseen the city's acquisition of road-blocking, cylindrical bollards and other barriers designed to prevent terrorists from driving into revelers on Bourbon Street during one of the city's many celebrations.

The barriers were part of a broader $40m public safety package announced by Miller's boss in those days, Mitch Landrieu, the city's mayor, who left office in 2018 and more recently served as the co-chairperson of Kamala Harris's presidential campaign.