Terror on Twitter, by P.W. Singer and Emerson Brooking (Popular Science)
How ISIS is taking war to social media-and social media is fighting back

http://www.popsci.com/terror-on-twit...o-social-media

The core of ISIS is seasoned veterans of the Iraqi insurgency that followed the 2003 U.S. invasion. Well versed in the power of the media, they have been joined by a new generation of Millennial recruits. The average age of foreign fighters who traveled to join ISIS is 24, meaning tools like Facebook, Twitter, and Instagram are what they've grown up with. In the context of global jihad, this is a dangerous combination.
The article then goes on to illustrate how ISIS is using social media (and most understand, it isn't limited to radicalization). After this the article explains how governments and non-government organizations like Anonymous are using social media to fight ISIS, with short but sufficient descriptions of doxxing, DDoS, sabotage, content alternating, twitter account hunting, etc.

Together, this loose coalition seeks to rob ISIS of one of its most powerful weapons: kicking it out of the very social-media ecosystem that helped give it life.
I have little faith that mass efforts of counter radicalization will every accomplish anything, and in many cases will backfire. However, denying, or even disrupting, ISIS's use of social media should have a telling effective when combined with effective law enforcement, intelligence, and military operations.