Recomendo a leitura integral deste texto (link via Mário Amorim Lopes), sem prejuízo de considerar que, economicamente, a zona euro seria mais – e não menos – credível com um mecanismo claro de insolvência e saída e que, do ponto de vista de países na situação da Grécia no contexto da União Europeia, há bons argumentos políticos (que eu subscrevo) para defender a saída do país em causa do euro: Mankiw and Conventional Wisdom on Europe. Por John Cochrane.
What is this “fiscal union,” apparently providing countercyclical Keynesian stimulus at the right moment? In the US, we have Federal contributions to social programs such as unemployment insurance. Europe has the common agricultural policy and many other subsidies. We do not have systematic, reliably countercyclical, timely, targeted, and temporary local fiscal stimulus programs. Just how big is the local cyclical variation in state or local level government spending or transfers? (And why does fiscal union matter so much anyway? If you’re a Keynesian, then local borrow and spend fiscal stimulus should be plenty. The union matters only when countries near sovereign default and can’t borrow.)
The local and cyclical qualifiers matter. Yes, both US and Europe have some pretty large cross-subsidies. But most of these are permanent. The rest of the nation subsidizes corn ethanol to Iowa year in and year out. Social security payments come year in and year out, and transfer money from states with workers to those with retirees. Monetary policy has at best short-run effects, so the argument for currency union has to be about local cyclical, recession-related variation in economic fortunes, not permanent transfers.
And Federal fiscal transfers only started in the 1930s. We had a currency union in 1790, and no substantial Federal fiscal transfers at all until the 1930s. How did we get along all this time?