Most of today's economic institutions, from money to banking, evolved over many years the unintended consequences of decisions by millions of individuals. By contrast, the eurozone stands out for being a deliberate creation.

The eurozone is a remarkable experiment, a genuine vanguard of global progress. As 2012 ends, it is in trouble, and every effort must be made to nurture and strengthen it.

By the second half of 2011, it was evident that emerging economies, which had weathered the financial crisis that began in 2008 moderately well, were taking on water as the eurozone crisis deepened. Growth slowed sharply in Brazil, India, China, and other countries.