After serving three terms in the Taito City Assembly [ja] (1979–1991) and two terms in the Tokyo Metropolitan Assembly (1993–1999) for the LDP, the NFP and finally the DPJ, he was elected to the House of Representatives in a 1999 by-election in Tokyo 2nd district.

The seat had been vacated when Kunio Hatoyama (then DPJ) resigned for his unsuccessful campaign for governor of Tokyo.

[2] In January 2012, he succeeded Osamu Yoshida as chairman of the House of Representatives economy, trade and industry committee (keizai sangyō iinkai, lit.

Later that year he followed Makiko Tanaka who was appointed to the cabinet as chair of the committee on foreign affairs.

Women across Japan formed an online protest group that initiated an e-mail campaign to demand an apology.