It is the deadliest attack by ISIS on the West in several years. But still, almost a week later, the group also known as Islamic State has yet to issue its trademark claim of responsibility for the horrific New Year’s violence in New Orleans.

A 9/11-style attack on the U.S. is unlikely now, he said, because ISIS and al-Qaida’s capabilities have been so degraded by U.S. and coalition efforts in the Middle East. “So they've looked to inspire individuals that already have access and in some cases,