But former George W. Bush White House counterterrorism adviser Fran Townsend, who heads a private group called the Counter Extremism Project, which has been sharply critical of Twitter, said the FBI and U.S. intelligence agencies have "plenty of other ways" to track IS tweeters. "The risk of recruitment and incitement to violence outweighs the benefits from surveilling them and finding out who they are," she said in an interview.