TOKYO -- Takako Doi, who in 1986 became the highest female role-model in Japanese political history but who never found the mainstream, resigned in defeat yesterday as head of her country's biggest opposition party.
Ms. Doi was accepting responsibility for a string of electoral defeats capped by a calamitous local election season this spring.
The announcement was in bleak contrast to a triumphant August day less than two years ago when the upper house of Japan's parliament made her the first woman ever chosen to be prime minister by either chamber.
On that heady day, with her party buoyed by scandals that had relentlessly racked the governing Liberal Democratic Party, she was the darling of television, basking in the klieg lights and the honors opposition parties had earned by smashing, for the first time ever, the LDP's majority in the House of Councillors, the upper house of the Diet.
Yesterday, Ms. Doi, 62, quietly announced her resignation in a private session with the other seven top leaders of her party.
She thus left vacant the leadership of a deeply divided party that has spent more than a year groping unsuccessfully for policies that could free it of its radical past and appeal to Japan's essentially conservative mainstream voters, many of whom are palpably weary of finding that only the LDP says what they want to hear. The party is expected to fill the vacancy at its convention late next month.
Her choice as prime minister by the upper house on August 9, 1989, had been little more than a gesture, for the decision lay with the House of Representatives, the lower house, where LDP control was secure.
But her spectacular rise from a career as a constitutional law professor gave hope to Japanese women, who had long been politically mute but whose votes against a scandal-ridden LDP were widely credited with helping to break the governing party's grip on the upper house.
"This day is the beginning of the end of the long dominance of Japanese politics by the Liberal Democratic Party," she promised.
As it turned out, that day was to be the high-water mark of her leadership of Japan's opposition.
Despite a half-year of negotiations, she could never bring her party far enough in from its traditional far-left positions to form an effective coalition with smaller mainstream opposition parties in the pivotal February 1990 lower house elections.
The coalition failed either to define a common policy or to put up enough candidates to form a majority in the lower house even if it had won every seat it contested.
The LDP ended up winning unexpectedly solid control of the lower house. Smaller centrist parties began to drift back toward cooperation with the LDP, trading off Diet votes on key national policy issues for political concessions from the governing conservatives.
Ms. Doi talked incessantly of the need to "reform and rebuild" her party, but she never made public a platform of change. Entrenched leftists seemed determined to block critical moves toward the mainstream.
Last fall, as Japan struggled to define a response to the Persian Gulf crisis, she seemed to fall back into the role of opposition for its own sake, waging high-visibility campaigns against the government's $13-billion cash contributions to the war despite opinion polls showing much public support and little disagreement.
By this year's local election season, the party's most tangible change was revision of its English name from Japan Socialist Party to Social Democratic Party of Japan.