Austan Goolsbee: No, there probably isn’t. If you look at the history, there have been places where what would seem to be not-optimal currency areas have stayed together. North and South Italy would seem to be one. But those tend to entail large, permanent subsidies from the rich side to the poor side, and a general social willingness to put up with these vast differences, usually because they’re all of the same nation state, and you have that mobility aspect. It’s harder to apply that model to Europe.