Antitrust populists increasingly call on the government to “break up big tech.” But antitrust enforcers would face heavy evidentiary burdens if they sought to break a company up on the premise that a long-consummated merger was unlawful from the outset and should have been blocked years ago....

Critics from both the right and the left claim that modern antitrust doctrine, rooted in consumer welfare, is inadequate to handle the challenges of the twenty-first century economy. They express nostalgia for 1960s antitrust, when the field had no clear objectives and cases were decided on...

In 1981, while in the FTC's Bureau of Consumer Protection, two of the authors were instrumental in initiating the FTC's fraud program, relying on Section 13(b)'s authority to obtain a permanent injunction to seek equitable relief, including asset freezes and consumer redress. The fraud program...