To answer these questions, the best starting point is the US. The model of a federal union that emerged from its history consists of a single currency managed by a federal agency; closely integrated markets for products, labor, and capital; a federal budget that partly, but automatically, offsets economic disturbances affecting individual states; a federal government that assumes responsibility for tackling other major risks, not least those emanating from the banking sector; and states that provide regional public goods but play virtually no role in macroeconomic stabilization.