A planned Hiroshima defence hub highlights how Tokyo is accelerating preparations to sustain its military should a Taiwan crisis reach Japan
9 Sep 2026
The risk of a conflict over Taiwan is shaping Japanese defence planning, with Tokyo shoring up security at home and abroad for a potentially prolonged fight. But there are economic, demographic and political constraints on how far its military transformation can go. In the second of a three-part series, Gabriel Dominguez examines how Tokyo is building military resilience within its territory. Japan’s recent purchase of a former Nippon Steel site to build a sprawling new defence hub points to a deeper shift in Tokyo’s preparations for a potential Taiwan conflict: it is increasingly planning not only for how to deter a war, but also for how to sustain the fight if deterrence fails.
The planned complex in Kure, Hiroshima prefecture – already home to one of Japan’s major naval bases – is intended to combine military facilities, logistics and defence production, concentrating several of the functions Tokyo would need to sustain its forces during a prolonged conflict. Four years into a sweeping defence build-up, experts say that emphasis on endurance reflects a grim conclusion taking hold in Japanese defence planning: preparing for a Taiwan crisis increasingly means preparing to defend Japan itself. Prime Minister Sanae Takaichi made that concern unusually explicit last November, saying a Taiwan contingency involving warships and the use of force could constitute a “survival-threatening situation” for Japan – potentially allowing its Self-Defence Forces (SDF) to act even if Japan itself had not come under direct attack. The geopolitical stakes far exceed the 110km (68 miles) separating Taiwan from Japan’s westernmost territory. Taiwan lies along vital Japanese sea lines of communication and at the centre of the first island chain, close to Japan’s southwestern islands and key US military installations. Should Beijing gain control, it could significantly strengthen the People’s Liberation Army’s (PLA) operational position around Japan and its access to the western Pacific.
Japan’s Maritime Self-Defence Force is expanding its capabilities and strengthening coordination with the US and other partners as Tokyo prepares for the prospect of conflict in the region. Photo: Kyodo News via AP Beijing sees Taiwan as a breakaway province to be reunited by force if necessary. Most countries, including the United States and Japan, do not see Taiwan as a sovereign state but are opposed to any forcible change to the cross-strait status quo.
US forces operating from bases in Japan could play a central role in a Taiwan conflict, potentially placing those facilities – and Japan itself – in Beijing’s crosshairs.
For a country whose post-war security policy has been built around constitutional pacifism and an exclusively defence-oriented posture, preparing to absorb and fight through such attacks marks a profound shift in military thinking. That pivot is likely to shape revisions to Japan’s National Security Strategy, National Defence Strategy and Defence Buildup Programme, which the government has brought forward to this year, just four years after the present documents were adopted.
The timing shows how quickly Japan’s defence transformation is moving. Tokyo is updating its three strategic documents a year ahead of schedule in response to what Takaichi described as “new ways of warfare” and a growing need to prepare for protracted conflict – developments she said were “accelerating across multiple domains”. That shift is also reflected in successive increases in military spending. The defence ministry is seeking 8.9 trillion yen (US$55.7 billion) for fiscal 2027, which would mark another record defence budget. The request identifies “sustained response capabilities” as one of three main pillars, alongside responding to “new ways of warfare” and strengthening the foundations of defence capability, including the defence production and technology base. Yet Tokyo draws an important line around what those preparations are intended to achieve.
Japan Ground Self-Defence Force soldiers observe a Type 88 surface-to-ship missile launcher, during joint military exercises with the US and the Philippines in Ilocos Norte province, northern Philippines, in May. Photo: Reuters Hirohito Ogi, a senior research fellow at the Institute of Geoeconomics in Tokyo and a former Japanese defence ministry official, said the strategic review was intended to strengthen Japan’s ability to defend its own territory, “not to promote an active Japanese role in a contingency over Taiwan”.
But Japan’s stated mission is different from the question of what kind of war its Self-Defence Forces are preparing to fight. Analysts say the capabilities being assembled suggest Japanese planners expect bases and communications to come under attack while forces must remain operational as ammunition, fuel and equipment are depleted.
Ogi said that because of Taiwan’s proximity and the strategic importance of Japan’s southwestern islands, a cross-strait conflict could spill over into an armed attack on Japan, depending on Beijing’s decisions. Japan’s concern over Taiwan is not new. Masashi Murano, a senior fellow at the Hudson Institute in Washington, said Tokyo had been shifting its military centre of gravity southwest since issuing its 2010 National Defence Programme Guidelines. What had changed were its assumptions about how a conflict with Beijing would unfold.
Murano said Japanese bases, ports and radar sites would probably come under large-scale missile attack in the opening phase of a conflict, while the PLA’s ability to strike US and Japanese forces and bases across the region could hamper US efforts to reinforce Japan. The more resilient those sites became, however, the harder it would be for Chinese planners to assume an opening barrage could quickly suppress Japan’s ability to fight or support US operations. By raising the prospect of a longer and costlier conflict, that resilience itself becomes a form of deterrence.
Type 90 battle tanks of the Ground Self-Defence Force take part in a live-fire exercise in Shizuoka prefecture, central Japan, in June. Photo: AFP This calculation is driving Tokyo towards weapons that can survive, disperse and impose costs despite the PLA’s numerical advantage.
Uncrewed systems could also help offset Japan’s manpower constraints. Murano said SDF personnel numbers were likely to decline, making affordable systems essential for fielding forces in greater numbers. The remote southwestern Nansei Islands are central to that strategy. For Murano, they are both territory to defend and positions from which dispersed surveillance systems, anti-ship missiles and one-way attack drones could threaten People’s Liberation Army forces moving through chokepoints between the East China Sea and the western Pacific Ocean. “Southwest island defence, long-range fires and Japan-US integration should be understood not as separate elements but as a single structure,” Murano said.
Michael Bosack, founder and director of the Parley Policy Institute in Melbourne, said Taiwan’s proximity to Japan would become even more significant as relatively cheap uncrewed systems proliferated. In a conflict, such systems could threaten ports, supply lines and commercial shipping – a particular vulnerability for trade-dependent Japan. Murano cautioned against relying too heavily on lessons from Ukraine, noting Beijing’s large missile arsenal and expanding bomber force. For Japan, he said, “the far more serious problem is the lack of an effective capability to counter PLA bombers” – particularly given vulnerable Japanese airfields and the PLA’s numerical advantage in combat aircraft. But denying access to a rival force is only part of the challenge. Japan is also preparing to keep fighting after taking losses.
The defence ministry has acknowledged shortfalls in the availability of ammunition, fuel and equipment for sustained operations, which is why Tokyo is expanding stockpiles and hardening facilities, including by moving key command centres underground. The Ground Self-Defence Force is also reorganising its logistics system to centralise the management of ammunition, fuel and other supplies, enabling their more flexible distribution in a contingency. Bosack said that combining concealment, dispersal and hardening – hiding assets, spreading them across sites and reinforcing facilities against attack – could frustrate Beijing’s operational planning, but warned that “Japan’s transparency in its security practice introduces additional risk”. PLA planners could glean information about new ammunition, fuel and weapons storage simply by following defence ministry engagement with local communities, he said, helping them update potential target lists.
For Murano, Japan’s stockpiling, acquisition of affordable uncrewed systems and pursuit of force survivability are “all premised on a protracted war of attrition lasting months”.
But he cautioned that preparing for a prolonged war would require more than stockpiling – Japan would also need a “defence innovation cycle” that rapidly fed battlefield lessons back into weapons and tactics, rather than treating sustainability simply as a question of how much ammunition had been stockpiled beforehand. Tokyo is already experimenting with faster equipment procurement. Less than three months after seeking interceptor drones in June, the defence ministry’s procurement agency selected Terra Drone’s Terra B1 and signed a mass production contract for delivery to the Maritime Self-Defence Force. Joint operations
The USS George Washington carrier strike group and Japan Maritime Self-Defence Force vessels sail in formation during the Valiant Shield exercise in the Philippine Sea in June. Photo: Handout Surviving PLA strikes would mean little if the SDF could no longer coordinate its operations, however. This realisation is driving changes in how Japanese and US forces plan to command operations during a potential crisis. The Japan SDF Joint Operations Command (JJOC), established in March 2025, created a permanent headquarters for joint operations, while Washington is turning US Forces Japan (USFJ) into a more operational “warfighting” headquarters. USFJ commander Lieutenant General Stephen Jost said in July that about 215 personnel had been added since the transformation began, including around 100 recent arrivals working to develop bilateral command procedures with the JJOC. The expanded headquarters now had enough personnel to sustain round-the-clock operations across key functions, Jost said. Tokyo is also investing in space capabilities, cyberdefence and resilient communications networks to maintain its ability to detect targets and transmit information should infrastructure and command nodes come under attack.
Murano said Japan should develop greater independence in the “kill chains” – systems used to find, track and strike targets – supporting its long-range weapons, rather than relying entirely on US systems. With the SDF becoming more dependent on unmanned platforms, he said, resilient space-based communications would become particularly important. That emphasis on resilience extends beyond the military. Tokyo is developing shelters in parts of the southwestern islands and plans its first field exercise next year to practise evacuating residents from remote Okinawan islands, including Yonaguni, in a military contingency. The measures underline how planning for a Taiwan conflict encompasses not only keeping the SDF in the fight but protecting civilians if hostilities reach Japanese territory.
And Japan’s ability to remain operational would have consequences beyond the defence of its own territory.
Murano cautioned that the phrase “a Taiwan contingency is a Japan contingency” did not mean the SDF would necessarily be assigned a mission to defend Taiwan. Japanese PM ‘open’ to talks with China
But Japan would be a critical platform for US forces that did.
If Japanese military infrastructure were disabled or Tokyo were coerced into dropping out early, Murano warned, the US would struggle to effectively support and defend Taiwan.
The PLA’s ability to strike Japanese and US targets across the region could therefore serve not only to physically disrupt their operations but also to exert “psychological coercion” aimed at making Tokyo drop out early – “before the war begins, if possible”, Murano said.
That makes the line between preparing to defend Japan and preparing for a Taiwan conflict increasingly difficult to draw.
For Bosack, planning around a scenario in which Japan remains untouched makes little sense.
“There may only be one scenario where Japan makes it through unscathed, and a thousand where it doesn’t,” he said.
Preparing for those scenarios requires more than making the SDF itself resilient. A prolonged conflict could rapidly consume missiles, drones and ammunition, while damaged equipment would need repair or replacement.
That brings Tokyo’s acquisition of the Kure site back into the equation. The defence ministry signed the contract with Nippon Steel in late August to acquire the former Setouchi Works site, where the planned hub is intended to combine equipment maintenance and manufacturing, logistics and operational facilities. The ministry has said integrating those functions will help increase the sustainability of SDF operations.
Japan’s recent purchase of a former Nippon Steel site in Kure, Hiroshima prefecture, to build a sprawling new defence hub points to a deeper shift in Tokyo’s preparations for a potential Taiwan conflict. Photo: Google Earth The development comes as the Japanese government is also considering a greater state role in defence production, including government-owned facilities operated by private companies.
The approach reflects a problem that stockpiling alone cannot solve: a prolonged conflict would require Japan to replenish weapons and ammunition, and repair damaged equipment. Tokyo increasingly describes its defence production and technology base as “defence capability itself”.
Beijing, however, sees the transformation very differently.
Responding to Japan’s 2026 defence white paper last month, the defence ministry in Beijing accused Tokyo of hyping the “China threat” to justify easing post-war restraints on its military, pointing to the accelerated revision of the three strategic documents, rising defence spending and longer-range strike capabilities.
Chinese officials have repeatedly described Japan’s trajectory as “remilitarisation” and warned of a revival of militarism, while accusing Tokyo of interfering in Beijing’s internal affairs over Taiwan.
Tokyo rejects that characterisation, maintaining that the capabilities it is acquiring are intended to deter attacks and defend Japanese territory.
For Ogi, the central task of the review is organisational rather than conceptual: integrating the missiles, drones and other capabilities envisaged in Japan’s 2022 defence strategy documents into how the SDF is structured and fights.
Tokyo may insist its military is not being built to defend Taiwan. But its preparations suggest that a war over the island could force Japan to withstand missile attacks, disrupted communications and months of high-intensity attrition simply to defend itself.
Stronger Japanese capabilities would in turn make Beijing “more hesitant to expand a conflict into Japanese territory”, Ogi said, and indirectly, make a successful PLA takeover of Taiwan more difficult.
For Bosack, that is ultimately the logic behind Japan’s preparations.
“At best, it deters China,” he said. “At worst, it prepares Japan for a conflict that will inevitably impact the country in significant ways.”