Japan's new Prime Minister, Naoto Kan, faces unenviable challenges. He was elected to the office by the Democratic Party of Japan following last week's sudden resignation by Yukio Hatoyama. Credited with fashioning the election victory of the centre-left DPJ only eight months ago, Mr. Hatoyama managed to become dramatically unpopular in record time. A controversy over financial irregularities during the election campaign destroyed the impression that the new government represented change from the sleazy money politics of the Liberal Democratic Party. But the trigger for Mr. Hatoyama's resignation was the U.S. military presence on the island of Okinawa. Of nearly 40,000 American troops in Japan under a bilateral security treaty, over two-thirds are in bases in Okinawa. The local population resents them. The DPJ made an election promise to reduce the number of U.S. troops in Okinawa, and specifically to move the Marine Corps Air Station Futenma off the island. The plan was fiercely opposed by the U.S., which sees its presence in Okinawa as vital; the island is located strategically close to North Korea and China. Public anger mounted when it became apparent that the U.S. carried more weight on this issue than voters, and that all Mr. Hatoyama could do was relocate the base to a less-populous area on the island. Across the rest of Japan, he was blamed for mishandling relations with an important international ally. With elections to the Diet's upper house due in less than a month, he opted to fall on his sword, leaving the mess to his successor.

Mr. Kan's credentials as a grass-roots politician, unafraid of entrenched interests, may help the DPJ regain some of its lost shine in time for the July elections. The party needs a majority in the upper house to reduce its dependence on allies for important policy decisions, especially on the ailing economy. With the Okinawa issue now an emotional lightning rod, Japanese voters are also likely to judge Mr. Kan on how he walks the tightrope of U.S.-Japan ties. The recent tensions between North and South Korea have shown how Japan is torn between its perceived need for the U.S. as the guarantor of its security and the growing feeling that it must cut its dependence on the superpower by improving ties with China and other neighbours. As well as heavy-duty domestic issues, Mr. Kan — Japan's fifth premier in four years — will need to deliver fast on this major foreign policy issue to prove that he can lead the country better than his predecessors.

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