The European state system, Leon Trotsky wrote in 1932, resembles “the ‘system’ of cages in an impoverished provincial zoo.” The European Union, the ideal of postwar reconstruction, was intended to replace the tariffs, borders, and belligerence of the old Europe. With the euro currency and the “four freedoms” of the movement of goods, people, services, and capital, it aspired to turn Europe into an economic safari park. Instead, the union has created a new set of problems and unleashed a political wildness that threatens its future.

The common currency impoverishes the states of the “southern tier” for the same reason it enriches users north of the Alps and Pyrenees, especially the zookeepers in Berlin and Brussels. The departure of jobs to Asia and the arrival of migrants from Africa and the Middle East have revived nationalism in the provinces, and the red-meat politics of bigotry too. The German economy has recovered since 2008, but the southern eurozone remains a wasteland of bailouts, enforced austerity, and unemployment levels last seen when Trotsky wrote that, in global economic terms, “Europe is on the downward trend.”