But, Mr. Connolly warns, once a mechanism is in place to transfer money from Germany to the current-account deficit countries, it's only a matter of time before Germany is faced with the question of adding France to its list of dependents something even Berlin may not be willing or able to afford.

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The U.S.-Canada Income Tax Treaty of 1980 does not provide a mechanism for the IRS to collect U.S. estate or generation-skipping transfer tax from the estate of an individual resident in Canada at the time of his death.

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Not only does this increase the political popularity of the program and provide a way to transfer some of the gains of immigration to the native born population, but it also serves as an enforcement mechanism.

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