In a major legal battle, the U.S. Justice Department is taking action against Google, a company that many people rely on for searching the internet. This case is crucial because it addresses how big companies can control entire markets and limit competition.

While the company has beat back European antitrust interventions by paying $7.1 billion, U.S. enforcers are now flexing their muscles — and the most painful part for the Alphabet Inc. unit won’t be monetary fines,