The deadly hostage crisis in Sydney, Australia is the latest in a series of attacks by mentally unstable criminals who claim to be fighting in the cause of Islamic extremism. CBS News security analyst Mike Morell, former Deputy Director of the CIA, sat down with CBS Evening News anchor Scott Pelley to discuss the impact the Islamic State's online propaganda is having. Morell said ISIS' social media ability is the most sophisticated security agencies have seen. Watch the video above to hear Morell describe the challenges created by this type of online propaganda.
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