Matt Olsen, former director of the National Counterterrorism Center, talks to Charlie Rose about the dangers posed by the group known as ISIS or ISIL -- including the estimated 100 Americans who have attempted to travel to Syria to fight alongside them. Olsen also talks about the NSA leaks, the Benghazi controversy and more in a full-hour interview, airing Oct. 8, 2014 on PBS. SUBSCRIBE to get the latest from Charlie Rose: http://bit.ly/CharlieRoseSUBSCRIBE Connect with Charlie Rose Online: Visit the Charlie Rose WEBSITE: http://bit.ly/CharlieRoseDotCom Like Charlie Rose on FACEBOOK: http://bit.ly/CharlieRoseFacebook Follow Charlie Rose on TWITTER: http://bit.ly/CharlieRoseTwitter Follow Charlie Rose on INSTAGRAM: http://bit.ly/CharlieRoseInstagram About Charlie Rose: Emmy award winning journalist Charlie Rose has been praised as "one of America's premier interviewers." He is the host of Charlie Rose, the nightly PBS program that engages America's best thinkers, writers, politicians, athletes, entertainers, business leaders, scientists and other newsmakers. USA Today calls Charlie Rose, "TV's most addictive talk show." New York Newsday says, "Charlie's show is the place to get engaging, literate conversation... Bluntly, he is the best interviewer around today." The NCTC's Matt Olsen on the Threat of ISIS (Oct. 8, 2014) | Charlie Rose / charlierose