As China Expands into the Pacific, Will Japan Play the “Nuclear-Powered Submarine” Card?

【Financial News, Tokyo—Correspondent Seo Hye-jin】The Japanese government is discussing whether to state in its national security strategy that it will consider acquiring nuclear-powered submarines, the Yomiuri Shimbun reported on the 7th. The plan is to strengthen deterrence against China’s maritime expansion with submarines capable of remaining submerged for long periods. Whether to proceed with an actual acquisition is expected to be decided over several years, following research and study.
The Yomiuri Shimbun reported that day, citing multiple Japanese government and ruling-party officials, that a plan to include a policy of considering the acquisition of nuclear-powered submarines for the Japan Self-Defense Forces (JSDF) in the three key security documents—including the National Security Strategy, all three of which are due to be revised this year—was gaining traction.
If the documents explicitly state that Japan will “consider possessing” such submarines, the groundwork will be laid for launching related research and studies. The Japanese government envisages conducting a review over the following several years before deciding whether to acquire them. It plans to carefully determine the specific wording for the security documents, taking into account recommendations from an expert panel and discussions within the ruling party.
The proposal to acquire the submarines stems from China’s expanding presence in the Pacific. Nuclear-powered submarines can remain submerged longer and travel faster than conventional submarines, making them better suited to patrol and surveillance missions across wide areas of ocean. Some in Japan argue that they could also improve mobility when Japan exercises its counterstrike capabilities, helping to strengthen deterrence.
Calls for Japan to possess nuclear-powered submarines were also voiced at the government expert panel discussing revisions to the security documents. The Japan Innovation Party urged their prompt acquisition in a proposal submitted to the government.
The ruling Liberal Democratic Party proposed using “next-generation propulsion” to enable Japan to possess submarines equipped with vertical launch systems (VLS) capable of firing long-range missiles. However, it did not specify the type of propulsion.
Cost and operating personnel are major challenges. The construction cost of a nuclear-powered submarine is expected to be several times that of a conventional submarine. Japan will also need to train specialists to maintain, service and operate nuclear propulsion systems.
With calls for caution also emerging from within the expert panel, the Japanese government plans to review the panel’s final recommendations and the ruling party’s position before deciding how much to include in the security documents.


[email protected] Seo Hye-jin Reporter