Social media must self-police for violence to preserve its unique value

Congressional Democrats are demanding that social media companies do a better job of policing threats against the FBI in the wake of the agency’s search of former President Donald Trump’s Florida residence for classified documents that he took from the White House. The issue presents a crucial test of those companies’ ability to weed out dangerous speech without trampling on the First Amendment. If the companies don’t respond transparently to these demands and make a stronger effort than they are currently making to detoxify their sites, they risk losing the unique protections they enjoy under...