ISIS and the ‘Internet Radicalization’ Trope

In The News Piece in The Atlantic
Dec. 8, 2015

New America ISP data is cited in an article about what motivated the San Bernardino attackers: 

"The group does exhort Western supporters to travel to its self-proclaimed caliphate, but according to a recent study of ISIS sympathizers in the West, no one returning from such a journey has yet committed violence in the United States."