In an interview on ABC's "This Week," Homeland Security Secretary Alejandro Mayorkas warned of a "very difficult threat landscape" after the New Orleans truck attack.

The New Orleans attack that killed 14 is thought to be the deadliest IS-inspired assault on U.S. soil since a 2016 massacre of 49 people inside Pulse, gay nightclub in Orlando, Florida.

In her mind, she still sees the bodies of the victims lying on the road and sidewalks. But as horrific as the attack was, McGrew watched the next night as tourists strolled down Bourbon Street,