Suddenly it is game on in Tokyo – and the world is watching. For the past 15 years Japan has been trying to shrink its way out of its problems. That did not work. Now it is about to try the opposite approach.

Japan’s “lost decades” have long been an awful warning to the world of the damage that a spectacular boom and bust can inflict on an economy’s long-term prospects. Now Japan could become another kind of example. If the pedal-to-the-metal reflationary policies of Shinzo Abe, the recently elected prime minister, succeed, there will be a profound impact on post-crisis policy making everywhere.

History shows that Japan rarely does things by half-measures. The financial bubble of the 1980s was probably the biggest in history. At its peak the Tokyo stock market was worth more than half of global market capitalisation.