Introduction

Andy Rain/European Pressphoto Agency

The British prime minister has called for a referendum on leaving the European Union. The president of Poland has suggested delaying until 2015 any decision about adopting the euro. When Britain, an “active member” of the union, and Poland, one of the newest member states, are both debating their involvement, it may be time to ask: Should the European Union continue as a monetary union, a political bloc, or neither? What are the obstacles to staying together, and what would be the obstacles to dissolving?