Why Attorney General Says ISIS Is More of a Threat Than al Qaeda

PHOTO: ISIS militants parade through Sirte, Libya in photos released by the Islamic State on Feb. 18, 2015.PlayIslamic State
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The nation’s top law enforcement official says the threat from ISIS is so great because the terror group's technologically advanced tactics are “still new to us," and the U.S. government is “still trying to determine the scope” of efforts to radicalize Americans and others around the world.

“It's as serious -- if not more serious a threat -- than al Qaeda,” Attorney General Loretta Lynch told ABC News’ Pierre Thomas in an exclusive interview. “It is a dangerous, high-tempo threat environment.”

That threat environment comes from ISIS’ unprecedented social media campaign on Twitter and elsewhere, using slick advertising and online messaging to encourage followers worldwide to launch attacks at home.

“They've got over 20,000 English-language Twitter followers,” Lynch noted.

Even with federal investigators looking at potential homegrown terrorists in every state, Lynch warned that new technology is making it harder than ever for authorities to identify and determine “who is going to succumb to the propaganda.”

“As people get drawn more and more into the rhetoric, they move off of [more mainstream] platforms … into encrypted platforms into which we don't have visibility,” she said, adding that federal authorities call it the “going dark” problem.

Even without that added challenge, Lynch acknowledged it’s difficult for the FBI to detect every so-called “lone-wolf” out there. She pointed to the recent attack in Chattanooga, Tennessee, where 24-year-old Mohammad Abdulazeez gunned down five military personnel.

“I think that the fact that he was not on law enforcement's radar illustrates the concern that we have of individuals who are outside the mainstream yet tap into these strands of thought or schools of thought that lead them to violence,” Lynch said.

She also cited a potential new threat from ISIS and others looking to harm the United States: a cyber-based terrorist attack.

“That is the thing that keeps me and many of my colleagues in law enforcement up at night,” Lynch said.