For generations, science fiction writers have been obsessed with the prospect of an AI Armageddon: a Terminator-style takeover in which the robots scour puny human cities, flamethrowers and beam cannons at the ready. Yet the more likely takeover will take place on social media. If machines come to manipulate all we see and how we think online, they’ll already control the world. Having won their most important conquest—the human mind—the machines may never need to revolt at all.
