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Japan's government is stepping back from plans to explicitly include the acquisition of nuclear-powered submarines in its three core security documents by year's end, instead considering a scaled-down commitment to launch related research.
The Asahi Shimbun reported Monday that the government is now strongly leaning toward suspending the option of writing submarine acquisition directly into the three security documents, and instead specifying only that it will begin research on the matter.
The shift stems from a divergence of views on nuclear submarine acquisition with coalition partner Nippon Ishin no Kai following recent party leadership reshuffles, which prompted calls within the government for more cautious deliberation.
The right-leaning Nippon Ishin no Kai had argued in a policy recommendation submitted to the government in June that Japan should acquire nuclear-powered submarines. Doing so would require amending Japan's three non-nuclear principles — enshrined in the constitution as a prohibition on producing, possessing or introducing nuclear weapons.
The Sanae Takaichi cabinet's pursuit of defense spending increases and revisions to the three security documents, without giving a clear answer on whether it would uphold the three non-nuclear principles, fueled widespread speculation that the administration was prepared to abandon them and move ahead with nuclear submarine acquisition. Prime Minister Takaichi had argued even before taking office, including in her writings, that Japan's ban on introducing nuclear weapons was unrealistic.
That led some observers to suggest that Nippon Ishin no Kai's policy recommendation was in effect window dressing designed to reflect the cabinet's own intentions. Yet Takaichi told a plenary session of the House of Representatives that "no decision has been made at this point regarding the adoption of a new propulsion system for submarines."
The Asahi interpreted the plan to launch research before formally committing to acquisition as a strategy to weigh the practical merits of actually introducing the submarines.
Nuclear-powered submarines cost around 1 trillion yen ($6.32 billion) per vessel to build, and experts say a minimum of three are needed for continuous operation when maintenance and training time are factored in — a scale of investment that has prompted calls for a rigorous cost-benefit analysis.
The potential to provoke China, which already accuses Japan of harboring militarist ambitions, is also cited as one reason cautious voices have emerged within the Liberal Democratic Party and the cabinet.
Meanwhile, Kyodo News reported that Japan's Defense Ministry is considering adding railways to the list of "public infrastructure" eligible for defense spending under its military buildup plans, and intends to include the importance of railway development in the three security documents. The rationale is to secure supply routes for Self-Defense Force units and transportation corridors for defense equipment in the event of a war or other contingency.
kate01@heraldcorp.com
