It began with a simple question: “Why on earth are US cell phone plans so expensive?” In pursuit of the answer, Thomas Philippon embarked on a detailed empirical analysis of how business actually operates in today’s America and finished up by overturning much of what almost everybody takes as read about the world’s biggest economy.

Over the past two decades, competition and competition policy have atrophied, with dire consequences, Philippon writes in this superbly argued and important book. America is no longer the home of the free-market economy, competition is not more fierce there than in Europe, its regulators are not more proactive and its new crop of superstar companies not radically different from their predecessors.

Philippon, a professor at New York University, is one of a list of brilliant economists of French origin now teaching in the US. Others include the recent Nobel-prize winner Esther Duflo, at the Massachusetts Institute of Technology, Olivier Blanchard, former chief economist of the IMF, and Emmanuel Saez and Gabriel Zucman, both now at Berkeley.