Minister of Defense (Japan) in the context of "Ministry of Defense (Japan)"

Shigeru Ishiba (born 4 February 1957) is a Japanese politician who served as Prime Minister of Japan and President of the Liberal Democratic Party (LDP) from 2024 until his resignation in 2025. He has represented Tottori 1st in the House of Representatives since 1996. Before his premiership, he was the Minister of Defense from 2007 to 2008 and Minister of Agriculture, Forestry and Fisheries from 2008 to 2009, as well as secretary-general of the LDP from 2012 to 2014.

Born into the Ishiba political family in Tokyo, Ishiba graduated from Keio University in 1979. Prior entering politics after his father's death, Ishiba worked at a bank before being elected to the House of Representatives in the 1986 general election as a member of the LDP at the age of 29. As a Diet member, Ishiba specialized in agricultural policy and defense policy. He served as parliamentary vice minister of agriculture under the premiership of Kiichi Miyazawa, but left the LDP in 1993 to join the Japan Renewal Party. After transitioning through several parties and returning to the LDP in 1997, Ishiba held various prominent positions, including Director-General of the Defense Agency under the premiership of Junichiro Koizumi, Minister of Defense under the premiership of Yasuo Fukuda and Minister of Agriculture, Forestry and Fisheries under the premiership of Tarō Asō.

Fumio Kishida (born 29 July 1957) is a Japanese politician who served as Prime Minister of Japan and President of the Liberal Democratic Party from 2021 until his resignation in 2024. He has represented Hiroshima 1st in the House of Representatives since 1996. Before his premiership, he was the Minister for Foreign Affairs from 2012 to 2017, as acting Minister of Defense in 2017, and he also chaired the LDP Policy Research Council from 2017 to 2020.

Born into a political family, Kishida spent part of his childhood in the United States, where he attended elementary school in New York City. After beginning his career in finance, Kishida entered politics and was elected to the House of Representatives at the 1993 general election as a member of the LDP. Kishida was appointed to Minister of State for Special Missions in the premiership of Shinzo Abe and Yasuo Fukuda from 2007 to 2008, and was appointed Minister for Foreign Affairs in 2012 after Abe regained the premiership following the 2012 general election, serving for five years and becoming the longest-serving Foreign Affairs Minister in Japanese history. Kishida resigned from the Abe cabinet in 2017 in order to head the LDP's Policy Research Council. Kishida also assumed leadership of the LDP's more moderate Kōchikai faction in 2012 following the retirement of faction leader Makoto Koga, a position he held until his resignation in 2023. Long considered a potential future prime minister, Kishida ran in the 2020 LDP presidential election, but lost to Yoshihide Suga. He ran again for the party leadership in 2021, this time winning in a second round run-off against opponent Taro Kono. Kishida was confirmed as prime minister by the National Diet four days later on 4 October 2021.

Yasuhiro Nakasone (中曽根 康弘, Nakasone Yasuhiro; 27 May 1918 – 29 November 2019) was a Japanese politician who served as Prime Minister of Japan from 1982 to 1987. His political term was best known for pushing through the privatization of state-owned companies and pursuing a hawkish and pro-United States foreign policy.

Born in Gunma Prefecture, Nakasone graduated from Tokyo Imperial University and served in the imperial navy during the Pacific War. After the war, he entered the National Diet in 1947 and rose through the ranks of the Liberal Democratic Party, serving as chief of the Defense Agency from 1970 to 1971 under Eisaku Satō, international trade and industry minister from 1972 to 1974 under Kakuei Tanaka, and administration minister from 1980 to 1982 under Zenkō Suzuki. As prime minister, he passed large defense budgets and controversially visited the Yasukuni Shrine. A conservative contemporary of U.S. president Ronald Reagan, Nakasone privatized the Japanese National Railways and telephone systems, and favored closer ties with the U.S., once calling Japan an "unsinkable aircraft carrier". After leaving office in 1987, he was implicated in the Recruit scandal, causing the influence of his LDP faction to wane before he retired from the Diet in 2004.

Shinjirō Koizumi (Japanese: 小泉 進次郎, Hepburn: Koizumi Shinjirō; born 14 April 1981) is a Japanese politician serving as the Minister of Defense since October 2025. He previously served as the Minister of the Environment from September 2019 to October 2021 and Minister of Agriculture, Forestry and Fisheries from May to October 2025. He has also served as a Member of the House of Representatives for the Liberal Democratic Party, representing Kanagawa since 2009. He is the second son of former Prime Minister Junichiro Koizumi and the younger brother of actor Kotaro Koizumi.

After graduating from university, Koizumi worked as a researcher at the Washington-based think tank Center for Strategic and International Studies, and became active politically as Young Leader of the Pacific Forum CSIS. He also spent time working as a political secretary for his father in the final years of his second term as prime minister. In the 2009 election, he was elected to the House of Representatives for the seat his father had occupied for more than 35 years.

Yoshimasa Hayashi (林 芳正, Hayashi Yoshimasa; born 19 January 1961) is a Japanese politician who has been serving as Minister for Internal Affairs and Communications since October 2025. Hayashi previously held six cabinet positions: Minister of Defence (August–September 2008), Minister of State for Economic and Fiscal Policy (July–September 2009), Minister of Agriculture, Forestry and Fisheries (December 2012 – September 2014, February–October 2015), Minister of Education, Culture, Sports, Science and Technology (August 2017 – October 2018), and Minister of Foreign Affairs (November 2021 – September 2023), and Chief Cabinet Secretary (December 2023 – October 2025).

A member of the Liberal Democratic Party, Hayashi was first elected to the House of Councillors in 1995, where he served for five terms until 2021. He resigned from the House to stand in the 2021 general election and has been serving as a member of the House of Representatives, representing the Yamaguchi 3rd district, since October 2021.

Taro Kono (河野 太郎, Kōno Tarō; born 10 January 1963) is a Japanese politician who served as the Minister for Digital Transformation from 2022 to 2024. A member of the Liberal Democratic Party (LDP), he previously served as Minister for Administrative Reform and Regulatory Reform from 2015 to 2016 and from 2020 to 2021, and was the Minister for Foreign Affairs and Minister of Defense under Prime Minister Shinzo Abe. He is also a member of the House of Representatives representing Kanagawa's 15th district since 1996.

Born in 1963 the eldest son of House Speaker and LDP President Yōhei Kōno, Kono grew up in a political family. Originally planning to study economics in Japan, he dropped out to attend Georgetown University, where he graduated with a Bachelor of Science in Foreign Service in 1983. After working in the private sector for more than a decade, Kono was first elected to the House of Representatives in 1996. In his career in the House, Kono served on various committees before running in the 2009 LDP leadership election; after losing to Sadakazu Tanigaki, he became Deputy Secretary-General of the LDP. After two years in the opposition, the LDP returned to power in the 2012 general election, while Kono remained a backbencher.

Tanzan Ishibashi (石橋 湛山, Ishibashi Tanzan; 25 September 1884 – 25 April 1973) was a Japanese journalist and politician who served as prime minister of Japan from 1956 to 1957.

Born in Tokyo, Ishibashi became a journalist after graduating from Waseda University in 1907. In 1911, he joined the Tōyō Keizai Shimpo ("Eastern Economic Journal") and served as its editor-in-chief from 1925 to 1946 and president from 1941. In the 1930s, Ishibashi was one of the few critics of Japanese imperialism, and became well known as a liberal economist. From 1946 to 1947, Ishibashi served as finance minister under Shigeru Yoshida. He was elected into the National Diet in 1947, but was purged for openly opposing the U.S. occupation policies; he returned to the Diet in 1952, after which he allied with Ichiro Hatoyama and served as his minister of international trade and industry. Ishibashi succeeded Hatoyama as prime minister in 1956, simultaneously serving as director of the Defense Agency, but resigned soon after due to ill health.