NO WESTERN democracy seems immune to today’s backlash against globalisation and economic liberalism. Since the financial crisis of 2008, distrust of markets and a renewed faith in the state has challenged the old orthodoxy and emerged as a resurgent political force. America has elected the protectionist Donald Trump. Britain entrusted leadership of the Labour Party to a far-left veteran, Jeremy Corbyn. Greece brought Syriza to power. Italy’s Five Star Movement helped to defeat Matteo Renzi. Yet, in one unlikely corner of Europe, mainstream politicians are defying the anti-market trend: France. France? At first glance, there could scarcely be a more improbable recruit for liberal economics. This is a country which romanticises a muscular anti-capitalist struggle, and whose people are more distrustful of globalisation than those anywhere else. Its public sector consumes 57% of GDP, six points above even that stripped-pine model of Scandinavian solidarity, Sweden. France teaches school pupils to answer such philosophy questions as “What do we owe the state?” One candidate for next spring’s presidential election uses the hammer and sickle as her logo—...