The European Union has demanded that Facebook, Google, and Twitter toughen up the way they deal with terror-related content, including a demand that they delete posts within an hour of them being flagged by law enforcement. National governments have been agitating for social-media companies to be liable for terror-related content posted on their sites—but the companies say such measures would curb freedom of expression and essentially allow governments to decide what’s posted online. The new EU guidelines are not legally binding, but officials said they would pursue formal legislation if they proved to be ineffective. European Commission official Andrus Ansip said: “While several platforms have been removing more illegal content than ever before—showing that self-regulation can work—we still need to react faster against terrorist propaganda and other illegal content which is a serious threat to our citizens’ security, safety and fundamental rights.”