Former Prime Minister Kiichi Miyazawa was a leader of postwar Japan's mainstream conservatism who strove to rebuild Japan while preventing it from retracing the militarist path. He died Thursday at 87.

Mr. Miyazawa joined the Finance Ministry in January 1942, one month after Japan went to war against the United States. In 1949 he became secretary to then Finance Minister Hayato Ikeda. As an aide to Mr. Ikeda while Mr. Ikeda was finance minister, a conservative party executive and then prime minister, Mr. Miyazawa took part in various Japan-U.S. meetings that helped shape Japan's postwar course — including preparatory talks for the peace treaty with its World War II adversaries and a 1953 meeting on the rearmament of Japan.

He received his first Cabinet portfolio in July 1962 as chief of the Economic Planning Agency under then Prime Minister Ikeda and pushed Mr. Ikeda's "double-the-income policy." After serving in ministerial posts in trade and industry, finance and foreign affairs, he became prime minister in November 1991. His political career and philosophy epitomized former Prime Minister Shigeru Yoshida's policy line of pursing economic reconstruction while firmly keeping Japan lightly armed under the war-renouncing Constitution.