Japan is considering a significant expansion of its military presence on remote Iwo Jima as growing Chinese naval activity beyond the First Island Chain raises concerns about the vulnerability of Pacific bases such as Okinawa.
Japan’s Defense Ministry plans to study upgrades to the island’s air and port infrastructure in the coming fiscal year, including extending the runway, strengthening port facilities and installing a floating pier capable of accommodating large vessels delivering construction materials and equipment.
Officials are also weighing the permanent deployment of Japan Self-Defense Forces (JSDF) fighter jets to enable rapid responses to foreign aircraft and warships operating near Japan’s eastern approaches. The move would complement Japan’s broader defense buildup across Okinawa and Kyushu and close what officials describe as a “surveillance gap” on the Pacific side of the archipelago.
Iwo Jima’s strategic location, about 1,200 kilometers south of Tokyo, gives Japan control over a vast exclusive economic zone and could help secure seabed resources, including rare earth minerals discovered near remote Pacific islands.
The planned upgrade also reflects concerns over increased Chinese military activity, including carrier operations beyond the First Island Chain and suspected seabed surveys that could map undersea cables or improve submarine operations.
However, construction faces logistical and environmental hurdles due to the island’s volcanic activity and its status as a historic World War II battlefield where thousands of Japanese and US troops died.
Adding to the strategic importance of Iwo Jima, Yoshihiro Inaba mentions in a December 2025 Naval News article that the island is the only one with a runway capable of supporting JSDF fighter jets in the Pacific theater. This makes the island a potential alternate base for JSDF fighters if Okinawa or Yonaguni airfields were degraded.
In this context, Japan’s plans to expand its military presence on the island may be linked to providing redundancy and defense-in-depth in case bases such as Okinawa were taken out by Chinese strikes during a US-China conflict over Taiwan.
The US Department of Defense’s (DoD) China Military Power Report 2025 states that China’s expanding arsenal of long-range precision strike weapons gives the People’s Liberation Army (PLA) the ability to threaten US forces far into the Western Pacific, with kinetic strikes potentially reaching 2,800–3,700 kilometers from mainland China, placing many US bases in the region, such as Okinawa and Guam, within range.
Pointing out Okinawa’s vulnerability to such an attack, Kelly Grieco and other writers mention in a December 2024 Stimson Center article that China’s growing arsenal of ballistic and cruise missiles could crater runways and taxiways at Japanese and US forward bases in Okinawa, such as Naha Air Base, Kadena Air Base and US Marine Corps Air Station Futenma, preventing aircraft from taking off or landing.
Grieco and others say that such an attack could close US bases in Japan to fighter operations for roughly 280 hours (about 11–12 days) and to tanker operations for around 800 hours (over 33 days), severely degrading US airpower early in a conflict.
The lack of airfield fortification also compounds the problem. Thomas Shugart III and Timothy Walton mention in a January 2025 Hudson Institute report that US bases in Japan, including those in Okinawa, are highly vulnerable to Chinese missile attack because they lack sufficient fortification and hardened infrastructure.
Shugart and Walton point out that many US aircraft operate in the open on ramps with limited protection, meaning precision ballistic or cruise missile strikes could destroy aircraft, fuel systems, and support infrastructure on the ground.
Situating Iwo Jima within a larger network of US and Japan Pacific island bases, solidifying Japan’s military presence on the island could boost the deterrent value of the US-Japan alliance, since every structure Japan builds there might also serve US forces.
Such ties in with the US Agile Combat Employment (ACE) concept, which disperses aircraft and support forces across numerous austere or temporary bases, enabling rapid movement and flexible operations to complicate enemy targeting and maintain combat effectiveness under attack.
Against this backdrop, Japan could be elevating Iwo Jima’s role as an air operations hub in the Second Island Chain, which spans the Bonin Islands, the Volcano Islands, the Marianas, and Western New Guinea.
However, within the Second Island Chain, Guam may be facing similar vulnerabilities to those of Okinawa. A US Government Accountability Office (GAO) report from May 2025 mentions that Guam remains vulnerable despite US missile defenses because its current defensive architecture is limited and still under development.
The report notes that the strategic island is presently protected mainly by a single Terminal High Altitude Area Defense (THAAD) battery consisting of six missile launchers and one radar, with additional protection occasionally provided by US Navy ships.
While the report says the US DoD plans to build a more robust integrated system—the Guam Defense System—to counter threats such as advanced ballistic, cruise, and hypersonic missiles, this capability will not be fully deployed until the late 2020s or early 2030s.
Furthermore, Lyle Goldstein argues in an October 2025 Defense Priorities article that while the US is building additional bases at Tinian and Palau as backups should Guam be taken out of action, these facilities are likely too few and too distant to make a major difference.
Goldstein also highlights China’s numerical strengths, arguing that aerial battles in a US-China conflict over Taiwan would occur within or near China’s home waters, rather than out in the Pacific, where the US Air Force holds the advantage.
Beyond that, several issues can be raised about the viability of the US ACE concept. Michael Blaser mentions in a July 2024 Proceedings article that ACE assumes unrealistic limits on enemy capabilities and underestimates advances in surveillance and strike technology.
First, Blaser points out that ACE depends on the adversary lacking sufficient long-range missiles to strike multiple dispersed airfields simultaneously. Yet, China’s large missile arsenal could attack many bases at once.
Second, he says that ACE assumes the enemy’s targeting cycle will be slower than US sortie generation. He mentions that AI, satellite surveillance, and automated imagery analysis could shrink the enemy kill chain to under 24 hours, allowing rapid targeting of dispersed aircraft.
Blaser warns that without deception and camouflage measures, ACE risks becoming ineffective against modern reconnaissance and strike systems.
Japan’s planned militarization of Iwo Jima reflects a shift toward deeper Pacific basing and operational redundancy to mitigate the vulnerability of frontline bases like Okinawa. However, the effectiveness of this strategy remains uncertain given China’s growing missile reach and the unresolved limitations of dispersed basing concepts.
