There are also encouraging signs that ISIS is losing momentum in its own propaganda efforts. An October 2016 study by the Combating Terrorism Center at West Point found that at its peak in August 2015, ISIS was responsible for circulating more than 700 distinct pieces of communication in a month. One year later, following some significant setbacks on the physical battlefield, that number was down to fewer than 200 in a month.
Robust content filtering
"Context really matters when you're talking about terrorism content," Bickert said. "Somebody can use the ISIS flag, a photo of the ISIS flag, and it may be the BBC saying this is something that ISIS has just done and there's a still image from one of ISIS' videos or something like that. That doesn't violate our policies. People can definitely come and talk about events of the day, but if somebody is using that ISIS flag -- an image of it to say, 'I like this group' or 'We ought to join this group,' or they're showing clips of an ISIS video and not clearly condemning it, that is something that violates our policies and we would remove it."
At Google, Walden stressed that the overwhelming majority of users have no sinister motives for using the company's services, and described the company's so-called community policing system as an effective tool for removing extremist content and other objectionable materials.
"[W]e know that community policing works," she said. "Content comes down quickly, and when it doesn't we escalate those things and make sure that it does.
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