One of the enduring ironies of antitrust law is that governments often step in to solve perceived problems that market forces are already addressing. A prime example: Standard Oil. Its grip on the oil market a century ago weakened not because of the 1911 antitrust breakup but due to newly discovered oil fields in the Midwest, which undercut its dominance.

Similarly, the breakup of AT&T in 1984 didn’t bring about the demise of the Bell telephone monopoly. The real shift came from new fiber-optic networks—launched around 1984—and the development of cellular networks. These rendered traditional phone monopolies obsolete. In these cases, as in others, antitrust enforcement proved costly but had little impact on market power.

Read my complete take at AEI.