Editor’s note: The text that follows is adapted from a speech delivered recently by the author to the Montreal Press Club.

On the op-ed page of The New York Times, former Central Intelligence Agency general counsel Jeffrey Smith recently argued that Donald Trump’s decision to revoke the security clearance of former CIA director John Brennan “violated Mr. Brennan’s First Amendment right to speak freely.” It’s an intriguing thesis. And, being a former lawyer who once wrote long law school essays about constitutional freedoms, I read it with keen interest.

But I also felt a twinge of nostalgia as I parsed Smith’s lawyerly arguments. Notwithstanding the nature of Mr. Trump’s treatment of Mr. Brennan, the gravest threats to free speech in democratic countries now have little or nothing to do with government action (which is what Constitutions serve to restrain). And with few exceptions, public officials now sit as bystanders to the fight over who can say what.

Last month, Facebook, Apple and Google deleted gigabytes of video, audio and text content from Alex Jones’s Infowars web site—part of a larger speech-pruning process that is applied every day to numerous (less prominent) wing nuts who, like Jones, blur the line between conspiracism and hate-mongering. Twitter, on the other hand, allowed Jones’s Infowarsand personal accounts to remain active—but then abruptly changed course in early September. Why? Who knows. All of these online services make users sign on to terms of-service agreements that prohibit abusive speech and the advocacy of violence. But the lines are blurry, and there’s lots of wiggle room. And even if there weren’t, it wouldn’t matter anyway since these are private companies that can pretty much ban anyone they want, so long as they’re willing to accept the blowback from remaining users. These companies aren’t making legal decisions when they block or don’t block one of their users. They’re effectively taking political positions on what is and isn’t beyond the bounds of mainstream discourse.