Ten years ago, Project Europe looked like a resounding success. A reunified Germany stood at the core of the world’s second-largest market, the European Union—an economic giant of 27 countries, many of which shared a common currency, the euro. Citizens of the EU were free to live and work in any member nation, and controls across most borders were light. For a time it looked as if the EU had achieved what Francis Fukuyama described as “the end of history.”
A version of this article appeared in the September 2016 issue (pp.114–115) of Harvard Business Review.