The expansionist essence of Japan's revision of the 'Three Security Documents'

Editor's note: Xu Weijun is an associate research professor at the Institute of Public Policy, South China University of Technology. His research interests include East Asian international relations, nationalism, China's diplomacy and China-US relations. The article reflects the author's opinions and not necessarily those of CGTN.

In recent years, Japan's defense policy has continued to move beyond the established boundaries of its post-war security system. The current round of revisions to the "Three Security Documents" (the National Security Strategy, the National Defense Strategy, and the Defense Buildup Program) promoted by Prime Minister Sanae Takaichi's government is not merely a policy adjustment, but rather a redesign of Japan's military capabilities, strategic positioning and framework for external security cooperation.

These revisions will not only shape the future direction of Japan's defense buildup, but also have a far-reaching impact on the security structure in East Asia, the strategic assessments of neighboring countries, and the regional military balance. As the Chinese Foreign Ministry stated, Japan is attempting to "chip away at the constraints imposed by Japan's constitution, international law and domestic legislation, renounce their obligations under international law and challenge the post-war international order."

Japan's intentions are very clear and its ambitions laid bare. The international community needs to remain highly vigilant against this dangerous trend.

Compared with the 2022 edition of the "Three Security Documents," the new round of revisions launched in 2026 does not represent a complete overhaul, but rather a deepening and acceleration of the course set in 2022. The 2022 documents marked a significant turning point in Japan's post-war security policy, focusing on loosening political constraints on defense policy and allowing principles to be breached. The 2026 revision is the implementation and further upgrade of the previous documents. Its core aim is to turn the capability goals proposed in 2022 into real operational capabilities, institutional arrangements and regional security influence. This path will push Japan to further break through the constraints of the post-war peace system, accelerate its transformation into a major military power and consequently have a stronger impact on security and stability in East Asia.

In terms of security strategy positioning, although the 2022 documents had identified China as "the greatest strategic challenge," the overall narrative still focused on maintaining national security and the international order. The 2026 revision shows a strategic tendency to actively shape the regional security order, seeking to expand its strategic role in the so-called Indo-Pacific security architecture through multiple channels. These include defense capability building, alliance coordination, defense equipment exports and the construction of economic security systems. This marks a shift in Japan's security strategy towards a more proactive, expansionist and offensive direction.

In terms of defense policy ideas, the key breakthrough in the 2022 documents was the introduction of "counter-strike capabilities." However, the Japanese government still stressed that the use of such capabilities must comply with the Constitution and the principle of an "exclusively defense-oriented policy," making it clear that these capabilities should not be equated with preemptive strikes. In comparison, the 2026 revision focuses on upgrading counter-strike capabilities into combat-ready operational capabilities. The revision is expected to cover how strike targets are identified, how command authority is allocated, how Japan and the US make joint decisions, how Japan secures ammunition, bases, communications and logistics, and how counter-strike capabilities are integrated with missile defense, unmanned operations, cyber and space capabilities. This implies that Japan is seeking to transform its so-called counter-strike capabilities from a policy concept into substantive military capabilities that are deployable, interoperable and sustainable in actual operations.

In terms of military buildup, the 2022 Defense Buildup Program used a catalogue of capability priorities as its core framework, in areas such as long-range strikes, air and missile defense, unmanned equipment, cross-domain operations, mobile deployment, ammunition stockpiles and the reinforcement of defense facilities. Its significance lay in setting the direction for Japan's defense buildup over the next five to 10 years. By contrast, the 2026 revision places greater emphasis on system-building and combat readiness, proposing the deployment of an integrated defense and counter-strike system to respond to large-scale saturation attacks, the development of next-generation powered submarines that can carry long-range missiles, and the establishment of sustained combat capabilities that can last for years. These steps shift the logic of Japan's defense buildup from "possessing advanced equipment" to "building a sustained combat system."

Japan's revision of the "Three Security Documents" will have a deep and multidimensional impact on the security landscape in East Asia.

On the one hand, it will exacerbate security tensions in East Asia and give rise to a new round of security dilemmas. Japan's security policy has completely departed from the principle of an "exclusively defense-oriented policy," which will continue to amplify the military and security concerns of neighboring countries. As Japan continues to improve its offensive military capabilities, neighboring countries may respond based on their own security assessments. They may strengthen their military capabilities, adjust military deployments, deepen security cooperation, or enhance their crisis response capabilities.

As a result, Japan's military expansion may prompt neighboring countries to take countermeasures, fuel an escalation of regional security competition, and plunge East Asia into a new security spiral.

On the other hand, security pressures surrounding China will rise remarkably, with risks concentrated in three key areas: China's Taiwan region, the East China Sea and Japan-US military integration.

Regarding the Taiwan question, as Japan further strengthens its military deployments in the southwestern islands, its long-range strike capabilities and its joint operational mechanisms with the US, its posture over the situation across the Taiwan Strait will become increasingly prominent. Japan's forward bases, intelligence and reconnaissance capabilities, logistical support, long-range strike firepower, and naval and air forces could all pose direct security threats to the region.

Regarding the East China Sea, the revised documents will provide Japan with clear policy authorization to strengthen its defense systems for outlying islands and its maritime and aerial surveillance capabilities. This will prompt Japan to undertake more confrontational deployments and patrol operations in the waters and airspace surrounding Diaoyu Dao, significantly increasing the security risks of accidental conflict between China and Japan.

Regarding the Japan-US alliance, if Japan's long-range strike capabilities become deeply integrated with US intelligence, command and target identification systems, Japan will be substantially embedded in the US strike chain. Even if Japan does not yet have a fully independent offensive operational system, it will become an important extension of the US military's forward combat capabilities.