Once again, Europe has a country at its centre that is too big for its neighbours. Merely by keeping on its best behaviour, Germany has managed to reawaken the historic "German problem". It has succeeded its way into a crisis. Ever since Greece's finances became a matter of public concern just over two years ago, Germany has been regaining its status as the leading power in Europe. It subjected itself almost a decade ago to a painful reform of its welfare state and a freeze in real wages that has made it as competitive an exporter as any country in the world, including China.