"It was very difficult for me to cause worry, anger and troubles for the people of Okinawa," former Prime Minister Yukio Hatoyama said. "But I could not force my way of thinking as prime minister."
Hatoyama and his Democratic Party came to power in 2009 pledging a more assertive diplomacy and social and economic reforms, including the moving of Marine Corps Air Station Futenma off Okinawa.
The party's victory ended a half century of nearly continuous rule by the Liberal Democratic Party, whose policies centered around a close defense partnership with the U.S. and relied heavily on a powerful bureaucracy.
The elite career bureaucrats at the foreign, trade, finance and other ministries didn't change even when prime ministers changed, and have been key in setting government policies.
Hatoyama's campaign promises quickly unraveled, and he was forced to step down last June after only eight months in office.
He told reporters Wednesday that the U.S. had "stood firm" on the base issue. But he said resistance was even stronger within the Japanese bureaucracy, which had spent years formulating a compromise that would move the base within Okinawa to Henoko, a less crowded area.
Hatoyama said Japan in the long run should defend itself without any foreign troops in its territory, but would still need to rely on its security alliance with the U.S., its most important ally.
Hatoyama, who remains a powerful figure in the ruling party, also criticized his successor, Naoto Kan, for reverting to an old-style dependence on the bureaucracy, such as pushing for a free trade agreement that he said failed to protect the agriculture and financial sectors.
His comments indicated deep divisions within the Democrats, who still lack experience in governance because of the Liberal Democrats' 55-year grip on power.
Hatoyama said efforts should be made to win understanding from the Okinawa people for the base's planned move to Henoko, but that could prove unsuccessful and Japan may be forced to look for other options.
The people of Okinawa have long complained about pollution, noise, crime and other problems resulting from the U.S. military bases across the island, which hosts more than half the 47,000 U.S. troops in Japan. The Futenma move is part of a bigger plan to reorganize the U.S. troop presence, including moving 8,000 Marines to the U.S. territory of Guam by 2014.