Foreign fighters prove dangerous in Iraq and back home

Sunni Iraqis make up the majority of ISIS's forces, but analysts say a growing number of foreign fighters are joining their ranks. That even includes some Americans. ISIS is producing videos that urge westerners to join the fight, and thousands may be answering the call. Pamela Brown looks at the danger these fighters pose on the battlefield and in their home countries.

What could be done about all of this? Anderson spoke with National Security Analyst Fran Townsend, who's a member of the DHS and CIA external advisory committees and Maajid Nawaz, a former Islamist militant who is now an author and chairman of the Quiliam Foundation.