"Sixteen of the European Union's 27 member states share an economic and monetary union (EMU) with the euro as a single currency. Based on a gross domestic product (GDP) and global trade and investment shares comparable to the United States, these countries (collectively referred to as the Eurozone) are a major player in the world economy and can affect U.S. economic and political interests in significant ways. Given its economic and political heft, the evolution and future direction of the Eurozone is of major interest to Congress, particularly committees with oversight responsibilities for U.S. international economic and foreign policies. Uncertainty about the future of the Eurozone grew in early 2010 as a result of the onset of a sovereign debt crisis in Greece that was intensified by fears that the crisis could spread to other heavily-indebted Eurozone members. These concerns, in turn, took on added significance because the euro is considered a cornerstone of the European integration process. One important cause of the crisis stemmed from flaws in the architecture of the currency union, including the fact that the EMU provides for a common central bank (the European Central Bank or ECB), and thus a common monetary policy, but leaves fiscal policy up to the member countries. Weak enforcement of fiscal discipline, over time, led to rising public debts, contributing to the 2010 Eurozone debt crisis."
CRS Report for Congress, R41411