Andy Rose (2000), followed by many others, has used the gravity model of bilateral trade on a large data set to estimate the trade effects of monetary unions among small countries. The finding has been large estimates: Trade among members seems to double or triple, that is, to increase by...

Continental trade blocs are emerging in many parts of the world almost in tandem. If trade blocs are required to satisfy the McMillan criterion of not lowering trade volume with outside countries, they have to engage in a dramatic reduction of trade barriers against non-member countries. That...