The problem is that creating a monetary union is a little bit like invading Russia. At first, there is rapid progress, as the French troops, Napoleon or the Wehrmacht found when they stormed the country, taking large tracts of land without much resistance. Then slowly, as the heavy winter sets in, the Cossacks and the Russian partisans start blowing up your convoys. Eventually you end up with blood on the snow and a hasty retreat. Recall the 1920s – after the Great War the Gold standard had created ‘the Roaring 20s’. Similarly, when Mexico and Argentina pegged their currency one to one on the US dollar, there was a flood of capital coming from the major surplus country – the United States – into Mexico and Argentina, creating the feeling of triumph, growth and investment. It was exactly the same in the Eurozone.