In Japan’s evolving defense posture in a rapidly changing regional security landscape, the country is set to operationally deploy its first batch of F-35B Lightning II stealth fighter jets to the southwestern region starting August 7, 2025. This marks a historic transformation of Japan’s military capability, blending advanced fifth-generation technology with a geographic strategy aimed at deterring growing threats from China and reinforcing regional stability.
The deployment is the result of a broader modernization effort formally laid out in the 2018 National Defense Program Guidelines and the Mid-Term Defense Program, which aimed to recalibrate Japan’s security architecture to meet modern challenges. Among the most consequential decisions from that plan was Japan’s procurement of 42 F-35B STOVL aircraft in addition to its expanded acquisition of the F-35A variant. Combined, these purchases position Japan to field a total of 147 F-35s, making it the largest international operator of the platform—a distinction of both political and military significance.
Unlike the F-35A, which requires conventional runways, the F-35B version is capable of Short Takeoff and Vertical Landing (STOVL). This allows it to launch from short or damaged airstrips and land vertically like a helicopter. The STOVL capability makes it uniquely suited for expeditionary missions, including those from naval platforms such as the Izumo-class helicopter destroyers, currently being converted into light aircraft carriers.
Manufactured by Lockheed Martin and developed under the U.S.-led Joint Strike Fighter program, the F-35B is the only fifth-generation aircraft that can operate in this way. It incorporates stealth, sensor fusion, networked data-sharing, and precision strike capability, and its deployment to Japan marks a turning point in Japan’s ability to project airpower from land and sea under contested conditions.
The first four Japanese-operated F-35Bs will be stationed at Nyutabaru Air Base in Miyazaki Prefecture on Kyushu, Japan’s southernmost main island. This base is strategically located close to the Nansei (Ryukyu) Islands chain, which extends from Kyushu to within 110 kilometers of Taiwan. These islands—particularly Okinawa, Ishigaki, and Yonaguni—form part of the first island chain, a geostrategic concept used by the U.S. and allies to contain Chinese maritime expansion.
The Nansei region is increasingly a flashpoint for military tension. China has stepped up air and naval operations in the area, frequently sending ships and aircraft through the Miyako Strait—an international waterway near Okinawa—and increasing pressure near the disputed Senkaku Islands (claimed by China as the Diaoyu Islands). These maneuvers often simulate blockades or amphibious assault scenarios, aimed at both Taiwan and outlying Japanese territories.
Deploying F-35Bs at Nyutabaru enhances Japan’s capacity to rapidly respond to contingencies across this volatile corridor. It provides the Japanese Air Self-Defense Force (JASDF) with advanced assets that can be forward-deployed, relocated quickly, and integrated into a multi-domain defense framework.
Equally significant is the maritime dimension of the F-35B’s deployment. Japan is undertaking extensive modifications to its two Izumo-class helicopter destroyers—the JS Izumo and JS Kaga—to enable them to operate fixed-wing aircraft for the first time since the end of World War II. The ships are being retrofitted with reinforced flight decks, ski-jumps, and heat-resistant coatings, all to support F-35B operations.
Once operational, these vessels will serve as light aircraft carriers, giving Japan the ability to project airpower well beyond the home islands. The F-35B’s ability to take off from these smaller platforms without the need for catapults or arresting gear provides Japan with a rapid response tool that is mobile, survivable, and deadly.
This development significantly blurs the line between defensive and offensive posture, and while Japanese policy still limits offensive strike doctrine, these changes unmistakably expand Japan’s reach and capability in the event of a regional crisis.
China’s ongoing military expansion is the primary catalyst behind Japan’s strategic transformation. The People’s Liberation Army Navy (PLAN) and PLA Air Force (PLAAF) have become frequent visitors to Japan’s southwestern periphery. Surveillance flights, drone incursions, and naval drills near the Nansei Islands have grown in scale and frequency.
In particular, Chinese reconnaissance drones and long-range bombers have conducted missions close to Japanese airspace, often prompting JASDF fighters to scramble. Japan intercepted more than 1,000 foreign aircraft in 2023 alone, most of them Chinese, according to Ministry of Defense reports.
Moreover, Chinese naval groups, often including aircraft carriers like the Liaoning and Shandong, have performed simulated strike runs near Okinawa, while amphibious assault drills near the Taiwan Strait raise concerns of a potential Taiwan contingency with direct spillover into Japanese territory.
In this context, the F-35B gives Japan the ability to respond preemptively, track and neutralize threats with electronic warfare, and maintain air superiority in zones where traditional airfields might be vulnerable to missile strikes or cyber disruptions.
The concept of distributed operations—spreading out forces to reduce vulnerability and increase resilience—is now central to Japanese military doctrine. The F-35B, with its STOVL configuration, fits neatly into this strategy. It can be dispersed across multiple islands, use makeshift or damaged runways, and redeploy in real time depending on the evolving battlefield.
This flexibility is crucial given the rise of precision missile systems like China’s DF-21D and DF-26 “carrier killer” missiles, designed to target fixed airbases and naval groups. Japan’s ability to conduct “bounce operations”—moving aircraft between short runways or ships—will complicate enemy targeting and enhance survivability in a high-threat environment.
Additionally, the F-35B is equipped with powerful ISR (Intelligence, Surveillance, and Reconnaissance) systems and fusion sensors, providing not only situational awareness for its pilot but also a real-time data stream to allied forces across the region. This supports the Joint All-Domain Command and Control (JADC2) architecture being developed by the U.S. military and partners, ensuring Japan’s forces are not operating in isolation.
Japan’s integration of the F-35B is not just a national decision but a regional one with alliance implications. As a key ally of the United States, Japan’s advanced capabilities complement American power projection in the Indo-Pacific, particularly as the U.S. shifts more naval and air assets to counter China.
Japan’s growing interoperability with U.S. platforms—such as the U.S. Marine Corps’ own F-35Bs stationed in Iwakuni—facilitates joint operations, logistics sharing, and coordinated missions. U.S. forces may, in the future, operate from Japanese-converted carriers or share maintenance infrastructure.
Beyond the U.S., regional democracies such as Australia, South Korea, and the Philippines increasingly see Japan as a security contributor rather than just a defense consumer. Japan’s ability to field fifth-generation aircraft across the first island chain sends a strong signal to allies and rivals alike that the regional balance of power is increasingly resilient.
While Japan’s pacifist constitution has historically limited its military scope, recent years have seen incremental reinterpretations. The 2015 security legislation, for instance, allowed Japan to engage in collective self-defense and broaden its cooperation with allies. The F-35B’s deployment—especially its operation from carriers—raises important constitutional and political questions, but also reflects a consensus shift in Japanese society toward more proactive defense.
Formerly cautious about outward military projection, public sentiment has evolved as the threat from North Korea’s missiles and China’s assertiveness become more visible. Defense spending, too, is rising: Japan plans to increase its military budget to 2% of GDP by 2027, aligning with NATO standards and doubling current levels.
This trajectory suggests Japan is preparing not just for defense, but for a regional leadership role in maintaining the rules-based order.
The August 2025 deployment of the first operational F-35Bs is only the beginning. Japan intends to scale up its F-35B fleet, potentially placing aircraft at forward airstrips on Ishigaki, Amami, or even Yonaguni Island, all close to potential flashpoints. Additionally, as Izumo and Kaga complete conversion, the number of carrier-capable Japanese aircraft is expected to rise, further transforming Japan’s maritime posture.
There is also talk of armed drone integration, hypersonic missile development, and cyber-electronic warfare capacity as Japan transitions into a multi-domain defense power.
The F-35B’s arrival is a symbol of Japan’s strategic identity—technologically sophisticated, agile, and deeply embedded in a web of alliances. It is a quiet but powerful signal to adversaries: Japan is no longer content with passive defense. It is ready, capable, and increasingly willing to act.
