The execution of Peter Kassig is the lastest crime by ISIS.
Kassig's beheading and many others were featured in a disturbing video distributing days ago. The beheadings are causing some in Washington to call for a review of U.S. policy on hostage-takings.
How should President Obama respond to "pure evil"?
Charlie Sennott, a veteran Middle East reporter, talks about the impact of ISIS beheadings and strategies for freeing hostages.
"To understand inside the warped mind of ISIS is impossible. This is one of the most dark, sort of death cults we've ever come across in the many years we've struggled with Islamic extremism," he said.
Sennott, co-founder of the GlobalPost and founder of GroundTruth Project, knew James Foley, the New Hampshire freelance journalist who was executed by ISIS in the summer.
He said the U.S.' policy on paying for hostages is failing because of miscommunication between the State Department, the FBI and families.
Politics
"We went through it to some extent with the Foley family in feeling just how incredibly powerless they felt," he said.
Sennott also talks about the recent Jerusalem synagogue attack that left five people dead.
Watch the above video for the complete interview.
