US antitrust law enforcers have Big Tech in their sights. Here's what's happening

U.S. antitrust law, out of the spotlight for two decades, has burst back onto the scene: The DoJ announced investigations of Big Tech, presidential candidate Elizabeth Warren has called for breaking up Amazon, and the Trump administration tried to block the merger of AT&T and Time Warner. Watch this video to see why antitrust is back and how the law works.