Overview
- Prime Minister Sanae Takaichi told parliament the government will "seriously consider" introducing nuclear-powered submarines for the Self-Defense Forces but has not made any legal or procurement decisions.
- Defense Minister Shinjiro Koizumi earlier urged a taboo-free debate on revising Japan's Three Non‑Nuclear Principles to allow discussion of nuclear propulsion for military vessels.
- Officials have floated mentioning nuclear-powered submarines as an option when updating Japan's core defense and security documents later this year, though no formal policy change has been announced.
- North Korea's KCNA and outside commentators condemned the move as a step toward nuclearization, and Chinese state-linked commentary warned it could breach postwar taboos and prompt regional arms competition.
- Nuclear-powered submarines use onboard reactors for far longer range and endurance than diesel boats, which defenders say would boost Pacific surveillance and deterrence but would require legal and political changes at home.