So what is the Japanese lesson now? In many ways, the analogy is no longer terribly helpful. That is partly because the pupils are in a worse pickle than the teacher ever was. The most vulnerable countries, such as Greece, now face a risk that Japan never did: that markets will lose faith in their creditworthiness. Japan, for all its woes, has benefited from a huge pool of domestic savings and investors happier to keep their money at home than abroad. Meanwhile, the scale of the global upheaval makes Japan’s problems, which had little impact overseas and took place against a backdrop of global growth, look small by comparison. And with huge deficits in so many nations, the risk of a sudden loss of fiscal credibility is more acute than it ever was in Japan.