The leaders of the European Union and its member nations are collectively circling their wagons against Greece and its mountain of public debt. Meanwhile, something far more interesting is going on in the corridors of the EU institutions: political and economic revisionism.

The seeds of the Greek crisis—or at least the euro-zone's Greek crisis—were planted in large part in Brussels long ago. In late 2009, Athens announced that its public deficit for the year would hit 12.7%...