The long-awaited terrorist massacre?

The main obstacle for ISIS doing shooting attacks in the US is that they may just blend in with all the other mass shootings in the US.
Imagine the interrogation:

"Why did you shoot all these people?"
"American women are sluts!"
"You're not really distinguishing yourself with that crazy complaint."

"So seriously, give us a unique reason: why shoot all these people?"
"Your government is CORRUPT!"
"Uh...concentrate and try again?"

"Okay, one last time, one good reason why haven't heard before: Why shoot all these people?"
"God demands it."
"Now you're trolling us."