Antitrust enforcement is not perfect. It does not always support competition. Sometimes govt creates monopoly power. Sometimes markets do. The question is in what circumstances real world AT institutions improve things in real world flawed markets. 1/x https://twitter.com/proffionasm/status/1254419798295040001

The alternative approach quickly devolves to antitrust as religion, not a body of law enforced by real people, with real incentives, and with imperfect information.

It is Nirvana Fallacy: AT enforcement always supports markets because it is “exactly supporting the market.” 2/x

The comparative institutional question is not only the right one. It is also much more interesting from an economic perspective than the blackboard econ approach of declaring all deviations from perfect competition or some other competitive ideal to be unlawful. 3/x

My own view is that there are plenty of places where the evidence shows AT can and does improve things. And we can and should continue, led by evidence, to evaluate the evidence to find others. Or to conclude AT made things worse, or that we made a mistake in enforcement. 4/x

Those admissions make our institutions stronger, not weaker. Running from admission of error, in my view, has been an unhealthy habit in AT institutions for a long time.

E.g., reluctance to show work or analysis or do closing statements bc we might be wrong! 5/x

That’s a bit of an aside, I suppose. But I do think a more frank discussion of where enforcement has worked and had not, allowing for heterogeneity in the answers across areas, is a much more fruitful path for AT institutions than “do you believe in AT or not?” 6/6