I don't understand one thing. People keep saying that Milton Friedman "predicted" this. However, what exactly approach to macroeconomics did he prescribed to the political union? Specifically, how did he wanted to deal with regions that have different economic growth? As I understand it, he was opposed to strong government and fiscal policies. So how do you resolve these problems on national level, if you can't have monetary policy and you don't want to have fiscal policy? To me it seems that he didn't really have any better solution.
I think he expected that people would move from high unemployment to low unemployment regions. In practice, I don't know how true this is. For instance, even in a culturally homogeneous countries such as England and Germany there are significant differences in unemployment rates between regions.
