Even without his academic background, his bizarre nickname — “the Alien” — and his eccentric wife, Yukio Hatoyama would be a bracingly unusual Japanese leader.

There is his political platform based on welfare spending and free education. There is his visionary foreign policy and his dream of an Asia united under a single currency. Above all, there is his massive parliamentary majority and his status as the first Japanese opposition leader to win an election outright.

But in other regards, Mr Hatoyama represents much that is regressive in Japanese politics. He was born into a life of wealth and privilege and, in a parliament notorious for the number of “hereditary” family dynasties, he is the most hereditary of all. He is not only the son and grandson, but also the great-grandson, of senior Japanese politicians.

Today Mr Hatoyama will be formally elected Prime Minister by the Diet, posing the urgent question: does such a man have what it will take to see through Japan’s transformation from a “one-party democracy” to a genuine multiparty system?

His great-grandfather was parliamentary Speaker, his father was Foreign Minister and his grandfather was Prime Minister and leader of the Liberal Democratic Party (LDP). His mother is the heiress to the fortunes of the Bridgestone Corporation, the international tyre company. This summer a Japanese magazine estimated Mr Hatoyama’s personal wealth at 8.6 billion yen (£57 million).

His education, an engineering degree at the University of Tokyo, followed by a PhD at Stanford in California, was as expected for a young man of his background.

Friends confirm the impression, and the inspiration for his “Alien” nickname, of an earnest, cerebral and unimpassioned man who does not naturally connect with the Earthlings around him.

Even after being elected to the Diet as a member of the LDP, he seemed a diffident politician. “I always had the feeling he was a Hamlet character,” said Gerald Curtis, of Columbia University, who has known Mr Hatoyama for 25 years. “ ‘To be or not to be? Should I be a politician or should I have stayed an academic?’ ”

Mr Hatoyama formed the Democratic Party of Japan (DPJ) in 1996. The party was generously endowed by his mother and the Bridgestone fortune. He led the party from 1999, but stepped down after three uninspiring years.

His second chance came unexpectedly this year when his predecessor, Ichiro Ozawa, was felled by a scandal. But the scale of Mr Hatoyama’s victory — 308 out of 480 seats — reflected his steady leadership in the final months.

His political platform has been laid out in detail: slash spending on bureaucracy and public works, spend the savings on education and child allowances, cultivate closer relations with China and an “equal” relationship with the US. He defines his philosophy as one of yuai, or “fraternity”.

Such talk has earned him the mockery of one tough former Prime Minister, Yasuhiro Nakasone. “Hatoyama only talks about friendship and love,” he said famously. “He’s just like Mr Whippy ice cream.”

Tomorrow Japan will begin to learn whether Mr Whippy will refresh Japanese politics or melt in its harsh sun.

Japan’s new cabinet

Hirohisa Fuji, 77, is reported to be the new Finance Minister. He held the same post in 1993-94

Katsuya Okada, 56, is set to be Foreign Minister, charged with building stronger links with Asia

Shizuka Kamei, 72, is tipped to be the Financial and Postal Services Minister. He is leader of Mr Hatoyama’s coalition partners, the New People’s Party

Naoto Kan, 62, is likely to oversee the National Strategy Bureau. The former DPJ leader is also expected to be named Deputy Prime Minister

Mizuho Fukushima, 53, is to oversee consumer and family affairs. The Social Democrat Party leader will be the only woman in the Cabinet

Source: Times database

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