Having gone through eight prime ministers in the past decade - and suffered from near-zero economic growth while doing so - Japan finally decided to try something different when choosing government leader number nine. The newcomer is Junichiro Koizumi, a veteran politician from an intensely political family who has insisted for years that old ways of governing must change. By the usually boring standards of the dominant Liberal Democratic Party, Mr Koizumi brings flamboyance and fashion to the job. He also brings some new ideas. If he manages to turn those ideas into policy, Japan may well end the stagnation that has plagued it for too long. The rest of the world hopes so. Once praised as potential powerhouse number one, Japan has become a global economic problem. It barely maintains its own high living standards and fails to do much for anyone else's economic health. Mr Koizumi has the right ideas. He wants to reform Japan's troubled financial system by disposing of dud bank loans, privatising the rich postal savings system and overhauling other financial institutions. He also hopes to break down obstacles to greater competitiveness, while seeking more foreign trade and investment. He believes Renault's overhaul of Nissan's troubled car factories is just what more of Japanese industry needs. Whether he can pull it off remains unknown. His restructuring almost certainly - in the short run - would increase unemployment, bankrupt some companies and force huge loan write-offs. The gains would come later. This would hurt some traditional LDP interest groups, which could well fight hard to block the new prime minister. His party's elders are known for protecting themselves and their key supporters above all else, no matter what it may cost the nation. On the other hand, Mr Koizumi's surprising win shows that the public is fed up with the depressing record of the LDP. This gives him a rare opportunity to launch new approaches to old problems. If he succeeds, the entire world economy will win.