The rising antitrust movement gathered Tuesday at Washington, DC’s gleaming new Marriott Marquis to figure out exactly how to confront the ascendant, unapologetically powerful forces of Silicon Valley. They had a high-profile guest: Justice Department antitrust boss Makan Delrahim.

The Trump Justice Department does have some antitrust bona fides, which Delrahim was quick to tout. Across town, at that very moment, a judge was preparing to rule as to whether AT&T could buy Time Warner, which Delrahim had brought suit to stop. And besides, he noted, the department recently prosecuted a bunch of tuna fish executives. But he wasn’t having any of these upstarts’ guff about breaking up the big tech platforms.

Delrahim’s argument was essentially that, while Google and Facebook are massive companies with vast reach, unless they harm consumers, the antitrust crowd literally doesn’t have a case.

“The suggestion is that perhaps enforcers should broaden the consumer welfare lens to think about effects on democracy or expression,” Delrahim said, paraphrasing an argument made by those who want to see Facebook and Google’s grip on the online advertising markets and news distribution moderated. “We shouldn’t go down that road. First, enforcement actions purportedly aimed at supporting our democracy carry too great a risk of inadvertently undermining our constitutional values. Second, we don’t need to go beyond the consumer welfare standard because it can get the job done on its own.”

Delrahim’s remarks were a rebuke to his hosts at the Open Markets Institute, who argue that…