Activists and lawmakers are pressing the Obama administration and social media companies to do more to fight the Islamic State's use of Facebook, Twitter and YouTube as weapons of war. Mark Wallace, CEO of the Counter-Extremism Project, a private nonprofit formed to fight online and financial support for terrorists, suggested that those who don't cooperate could at some point be seen as offering material support for terrorist groups, which is illegal under U.S. law. "At some point you'd have to be responsible," Wallace, a former U.S. ambassador to the United Nations, told the Washington Examiner.