The Constitutional Revision Research Project seeks to follow, analyze, and document constitutional discussion in Japan.
Mainichi ShimbunThe Constitution of Japan (also known as the Postwar Constitution) went into effect in 1947, replacing the Meiji Constitution of 1890. It is recognized as the oldest unamended constitution in the world as of 2022, having never undergone revision in over 70 years since its promulgation. Throughout this time, constitutional revision has become an important subject of vigorous debate and discussion in Japan and around the world.*
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Japan LDP vote: Takaichi wins, will likely be first female premier - as it happened
October 2025
“In a historic first, Japan's ruling party chose hardline conservative Sanae Takaichi as its new leader, putting her on course to become the country's first female prime minister.”...
[Source: Reuters.]
*During the LDP leadership race, Takaichi expressed her willingness to broaden the ruling coalition to include parties aligned with her views on constitutional revision and foreign and security policy (see related coverage by Jiji Press).

Photo: Reuters/Kim Kyung-Hoon
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