He crisply summarises the results: “First, US markets have become less competitive: concentration is high in many industries, leaders are entrenched, and their profit rates are excessive. Second, this lack of competition has hurt US consumers and workers: it has led to higher prices, lower investment and lower productivity growth. Third, and contrary to common wisdom, the main explanation is political, not technological: I have traced the decrease in competition to increasing barriers to entry and weak antitrust enforcement, sustained by heavy lobbying and campaign contributions.”
All this is backed up by persuasive evidence. Those prices of broadband access in the US are, for example, roughly double what they are in comparable countries. Profits per passenger for airlines are also far higher in the US than in the EU.
The analysis demonstrates, more broadly, that “market shares have become more concentrated and more persistent, and profits have increased.” Moreover, across industries, more concentration leads to higher profits. Overall, the effect is large: the post-tax profit share in US gross domestic product has almost doubled since the 1990s.