As to the first, the protection [through antitrust enforcement] of the small businessman comes at a high price. It forces consumers to do business with small firms that may well have a local geographical monopoly, which would be undercut by a larger firm offering better goods at lower prices. Today the entry of such a competitor often comes from online merchants, like Amazon, that sell to everyone anywhere, and it is hard to think of any sensible restriction on Amazon’s business practices that would produce a net social benefit, given the many underserved areas in the United States. In addition, Amazon is always vulnerable to other online sellers that can take advantage of their skills in niche markets. Finally, a big entrant doesn’t always destroy local businesses. The dominant firm could be the anchor tenant at a shopping mall, for instance, whose presence makes way for smaller businesses offering complementary goods and services. What is more, the high administrative and compliance costs involved in Mr. Wu’s aggressive antitrust regime could easily exceed whatever gains in market efficiency he is aiming for.