This essay provides a perspective on the role of antitrust law in protecting and fostering competition in the digital economy, with particular attention to online platforms. It highlights the danger of anticompetitive exclusionary conduct by dominant online platforms and describes ways that antitrust law can challenge and deter such conduct. The essay also identifies a number of difficulties that U.S. courts and enforcers face in challenging harmful exclusionary conduct by dominant platforms, and discusses some ways that regulation can supplement antitrust law in fostering competition.

中文翻译：

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保护和促进在线平台竞争：反垄断法的作用

本文提供了反垄断法在保护和促进数字经济竞争中的作用的视角，尤其是在线平台。它强调了占主导地位的在线平台的反竞争排他行为的危险，并描述了反垄断法可以挑战和阻止此类行为的方式。本文还指出了美国法院和执法者在质疑主导平台的有害排他性行为时面临的一些困难，并讨论了监管可以补充反垄断法以促进竞争的一些方式。