The devil sitting on their shoulders, saying "kill, kill, kill."

Kevin Johnson writes in USA Today,

In a dramatic assessment of the domestic threat posed by the Islamic State, FBI Director James Comey said Thursday there are "hundreds, maybe thousands" of people across the country who are receiving recruitment overtures from the terrorist group or directives to attack the U.S.

Comey said the Islamic State, also known as ISIL, is leveraging social media in unprecedented ways through Twitter and other platforms, directing messages to the smartphones of "disturbed people'' who could be pushed to launch assaults on U.S. targets.

"It's like the devil sitting on their shoulders, saying 'kill, kill, kill,''' Comey said in a meeting with reporters.

...Bruce Hoffman, a longtime terrorism analyst and director of Georgetown University's Center for Peace and Security Studies, said in a recent interview that ISIL's multifaceted outreach and leveraging of social media is threatening to "outpace the government's capabilities across the intelligence community.''

"It's like the Dutch boy sticking his fingers in the dike,'' Hoffman said.

Indeed, Comey said that ISIL recruiters operating from safe havens in Syria are making initial contacts with recruits, mostly on Twitter, and are then "steering'' them into encrypted venues where their subsequent communications are "lost to us.''

"The haystack is the entire country,'' Comey said. "We are looking for the needles, but increasingly the needles are unavailable to us. ... This is the 'going dark' problem in living color. There are Elton Simpsons out there that I have not found and I cannot see.''

Comey said agents are working hundreds of investigations around the country involving suspected homegrown violent extremists.The director said the inquiries are open in all 56 of the FBI's field divisions.

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