A YEAR ago, Japan's parliament approved a resolution to move the nation's capital out of Tokyo.But as one prominent politician, Shintaro Ishihara, stated afterward, "When we voted for it, we were laughing all the way." Few Japanese seriously believe their government will help de-congest Tokyo by transplanting itself to another site. The plan's opponents - bureaucrats, the Tokyo government, and national legislators from the city - have so far blocked a national consensus to implement the idea. But one man, Keijiro Murata, a member of the lower house and of the ruling Liberal Democratic Party, has been quietly working for more than a quarter century to achieve a transfer of the capital. He predicts the plan will start within three years. The main reason: More people see Japan as too vulnerable if another disaster should hit the city, whose wealth and importance now help shape the world economy. Just in this century, the city has been destroyed twice, first by the 1923 quake and then by American bombs in 1945. "If it's happened twice, it can happen three times," Mr. Murata says. Some geologists predict an earthquake near Tokyo by the early 21st century. "Tokyo has become too concentrated with people, finance, resources, and companies," he says. "The risks are too high now." Added to the concern is the recent explosion in property prices that has eliminated the prospect of home ownership for about one-third of the city's young adults within their lifetimes. Resentment is also rising in rural areas that have fallen further and further behind Tokyo. Murata measures the public pulse by counting popular songs - anti-Tokyo tunes have become more common. Democracy will not flourish if more power is concentrated in Tokyo, he says. Centralization has served its purpose and is now causing damage, he adds. A national committee to promote the capital's transfer was set up among the nation's politicians and others 15 years ago, and now has 226 members. In 1988, 79 national bureaucracies were chosen for relocation to various sites around the country, but resistance has resulted in only a few small transfers. Murata wants to create a new capital, like Brasilia or Washington, of about 45,000 acres and up to 1 million people, perhaps near the cities of Kyoto, Niigata, Sendai, or Nagano.