Italy’s Chamber of Deputies  at Palazzo Montecitorio  in Rome.  Today’s northern European countries are running up record current-account surpluses, just as some southern European countries are experiencing Weimar-level unemployment. For Italy, Europe’s fourth-largest economy, the slump is deeper than 80 years ago. Photograph: Franco Origlia/Getty Images

Charles P Kindleberger, the great economic historian, once noted that the Great Depression was so deep and so long because of “British inabilit(...)