Sen. Amy Klobuchar recently invoked David and Goliath when discussing her fight to pass antitrust legislation to rein in dominant tech firms. “I have two lawyers. They have 2,800 lawyers and lobbyists,” she said at this year’s Code Conference in September. But executives at those dominant tech firms would do well to remember that Goliath ultimately lost to David.

Whether or not Klobuchar’s legislation makes it to a vote this term, we’ve crossed a Rubicon. Whatever legitimate (or illegitimate) concerns may be raised about the precise wording of the bill, the fact is that Europe has already prohibited dominant tech platforms from thwarting competitors in search services, operating systems, app stores, online retail and numerous other digital markets.

It would be irresponsible for U.S. policymakers to sit on the sidelines and let others set the rules—a fact perhaps recognized by the 242 members of the House of Representatives who voted in favor of the Merger Filing Fee Modernization Act, designed to strengthen antitrust enforcement. While that bill did not single out big tech companies, it passed in spite of significant opposition from the likes of Google and Amazon, a sign that lawmakers are no longer afraid to move against the industry’s wishes.