Yubari, Hokkaido, claims several distinctions, few of them enviable. It is Japan's only bankrupt city, and also its most elderly. Forty-one percent of its sagging population of 13,000 (down from 117,000 50 years ago) is aged 65 or over. That's of nationwide significance because within 40 years, Japan, demographically if not economically, will be one big Yubari. By 2050, barring a massive influx of young immigrants, not at present foreseeable, or a sudden baby boom, equally unlikely, 40 percent of Japan's shrinking population too will be 65 or over.

One asset Yubari has that Japan lacks is youthful leadership. The country's most elderly city boasts its youngest mayor. Naomichi Suzuki is 30 and an outsider. He's from Saitama originally, and began his working life as a career bureaucrat with the Tokyo prefectural government. When Yubari declared bankruptcy in 2007, the call went out for volunteer administrators to help set the debt-ridden city back on its feet. Suzuki's hand went up. It was to have been a two-year posting. But Suzuki took to Yubari, and Yubari to him. Municipal elections loomed in 2011 and he was persuaded to run. Give up vibrant Tokyo for a dwindling rural backwater? Give up a ¥5 million salary for a ¥3 million one? Crazy — or maybe the better word is unconventional, and if ever unconventional thinking is called for, Yubari provides a classic example.

He ran, and won. The prize? The chance to run a city ¥35 billion in the red and administer an 18-year financial reconstruction plan whose main features are higher taxes and slashed-to-the-bone social services.