Tanaka is chairman of the Institute for International Strategy at the Japan Research Institute, Ltd. and a senior fellow at the Japan Center for International Exchange. He has also been a visiting professor at the Graduate School of Public Policy, University of Tokyo, since April 2006. He was Deputy Minister for Foreign Affairs of Japan until August 2005. He had previously been Director-General of the Asian and Oceanian Affairs Bureau (2001-02) and the Economic Affairs Bureau (2000-01); Consul-General in San Francisco (1998-2000); and Deputy Director-General of the North American Affairs Bureau (1996-98). He was Director for Policy Coordination of the Foreign Policy Bureau, Political Minister at the Japanese Embassy in London (1990-93), a research associate at the IISS, London (1989-90), Director for North East Asian Affairs (1987-89), and Director for North American Affairs (1985-87). He has a B.A. in law from Kyoto University and B.A./M.A. in PPE from Oxford University.
Tanaka has contributed many articles to various newspapers and monthly magazines. His latest publications include [Reimagining Japan] (2011), Purofeshonaru no Kosho-ryoku [The Logic of Strategic Negotiation] (2009), Gaiko no Chikara [The Power of Diplomacy] (2009) and Kokka to Gaiko [The Nation and Diplomacy] (2005).