Para quem estudou Áreas Monetárias Óptimas*, estes são tempos históricos.

Só hoje, o Negócios fala no Euro só para os ricos, nas discussões Franco-Alemãs para uma Zona Euro mais pequena, num Comissário Europeu a prometer “problemas” para Portugal se não cumprir as metas acordadas com Bruxelas e no desejo de Bruxelas de “inspeccionar as contas da CP, Parque Expo e ANAM.

Se querem perceber o assunto, Mundell explica. Leiam as condições para as OCAs:

The four often cited criteria for a successful currency union are:^[5]

• Labor mobility across the region. This includes physical ability to travel (visas, workers’ rights, etc.), lack of cultural barriers to free movement (such as different languages) and institutional arrangements (such as the ability to have superannuation transferred throughout the region) (Robert A. Mundell). In the case of the Eurozone, while capital is quite mobile, labour mobility is relatively low, especially when compared to the U.S. and Japan.
• Openness with capital mobility and price and wage flexibility across the region. This is so that the market forces of supply and demandautomatically distribute money and goods to where they are needed. In practice this does not work perfectly as there is no true wage flexibility. (Ronald McKinnon). The Eurozone members trade heavily with each other (intra-European trade is greater than international trade), and most recent empirical analyses of the ‘euro effect’ suggest that the single currency has increased trade by 5 to 15 percent in the euro-zone when compared to trade between non-euro countries.^[6]
• A risk sharing system such as an automatic fiscal transfer mechanism to redistribute money to areas/sectors which have been adversely affected by the first two characteristics. This usually takes the form of taxation redistribution to less developed areas of a country/region. This policy, though theoretically accepted, is politically difficult to implement as the better-off regions rarely give up their revenue easily. Theoretically, Europe has a no-bailout clause in the Stability and Growth Pact, meaning that fiscal transfers are not allowed, but it is impossible to know what will happen in practice. Of course, during the 2010 European sovereign debt crisis, the no-bailout clause was de facto abandoned in April 2010.^[7]
• Participant countries have similar business cycles. When one country experiences a boom or recession, other countries in the union are likely to follow. This allows the shared central bank to promote growth in downturns and to contain inflation in booms. Should countries in a currency union have idiosyncratic business cycles, then optimal monetary policy may diverge and union participants may be made worse off under a joint central bank.