Twenty years on, what is euro's future?

The euro turned 20 years old on January 1, 2019. On January 1, 1999, after years of preparations, 11 member-states of the European Union agreed to use the same currency in all monetary transactions among themselves, an initiative that marked the official launch of the euro. The euro's introduction in physical form, as coins and banknotes, however, took place on January 1, 2002. The euro was broadly accepted as a unifying institution and another eight members joined the club in the years that followed.

Greece entered the Exchange Rate Mechanism (ERM) on March 14, 1998, and the Economic and Monetary Union (EMU) on January 1, 2001. Those opposed to the decision to join the euro area argued that Greece would no longer be able to control its fiscal policy. But Greece was not, and is not, like Sweden and Denmark, which did not adopt the euro. It was not a country with a stable...