Japan's Counterattack Capability Becomes Reality: Initial Deployment of the Type 25 Anti-Ship Guided Missile and Hypersonic Glide Missile and Its Strategic Significance

On March 31, 2026, Japan's Ministry of Defense reached a groundbreaking turning point in its post-war defense policy. The Japan Ground Self-Defense Force completed the first operational deployment of two domestically developed long-range missile systems: the Type 25 Anti-Ship Guided Missile (formerly known as the Type 12 Anti-Ship Guided Missile Capability Improvement Type) and the Type 25 Hypersonic Glide Projectile (HVGP). The Type 25 Anti-Ship Guided Missile was deployed at the Kengun Garrison in Kumamoto Prefecture, while the Type 25 HVGP was stationed at the Fuji Garrison in Shizuoka Prefecture. This deployment signifies the first concrete realization of the "counterstrike capability" acquisition policy outlined in the revised National Security Strategy (NSS) of December 2022.

The range of the Type 25 Anti-Ship Guided Missile has been significantly extended from approximately 200 kilometers of the previous Type 12 Anti-Ship Guided Missile to about 1,000 kilometers. With this range, it becomes possible to target extensive maritime areas in the East China Sea and military facilities on the opposite shore from launch points in Kyushu and the southwestern islands. The Ministry of Defense plans to deploy the Type 25 HVGP to the Kamifurano Garrison in Hokkaido and the Ebino Garrison in Miyazaki Prefecture within the fiscal year 2026. Furthermore, development is underway for ship-launched and air-launched variants of the Type 25 SSM for the Japan Maritime Self-Defense Force and the Japan Air Self-Defense Force, with the expectation of building multi-axis strike capabilities in future joint operations.

The Type 25 HVGP belongs to the category of hypersonic weapons, which Japan is introducing for the first time. This gliding weapon, characterized by high-speed flight, possesses high maneuverability that makes it difficult for enemy air defense networks to intercept. The initial deployment is primarily intended for doctrine development and training, but its mere existence serves as a deterrent. According to the Ministry of Defense, the range of the HVGP is said to reach several hundred kilometers, although exact figures have not been disclosed.

On the other hand, there are obstacles to Japan's counterstrike capability development. The introduction plan for Tomahawk cruise missiles is showing signs of delay. Reports indicate that the United States' operational use of Tomahawks against Iran in early 2026 has affected the delivery schedule to Japan due to the need for stock replenishment. The Japanese government has signed a contract to purchase up to 400 Tomahawk Block V missiles, which were planned to be deployed on Aegis destroyers. This delay is noteworthy as an example of how the military actions of allied nations directly impact Japan's defense modernization plans.

The severity of the security environment is also reflected in numbers. According to the Ministry of Defense, the Self-Defense Forces conducted a total of 11 weapon protection activities to safeguard foreign military vessels and aircraft during 2025. This marks an upward trend from the previous year and is analyzed as a response to the increased activities of the People's Liberation Army of China around the southwestern islands and the continued ballistic missile launch tests by the Korean People's Army. While the Chinese military has intensified military exercises around Taiwan, it has also maintained a normalized military presence around Japan's remote islands, making the strengthening of Japan's southwestern defense posture an urgent issue.

Reactions from neighboring countries to Japan's shift in defense policy are also noteworthy. On April 7, Chinese Foreign Ministry spokesperson Mao Ning expressed grave concern during a regular press conference regarding the proposed revision of Japan's three principles on the transfer of defense equipment, criticizing it as a serious violation of international legal documents such as the Cairo Declaration and the Potsdam Declaration. The proposed revision relaxes export rules that had previously been limited to non-combat defense equipment, making the export of lethal weapons generally permissible. Additionally, it includes provisions for exceptions for exports to conflict parties and changes the requirement for prior approval from the Diet to post-reporting. This revision is positioned as a fundamental shift in Japan's post-war arms export policy and has sparked debate both domestically and internationally.

Experts, including former Self-Defense Force personnel and military journalists, point out that Japan is gradually transitioning from the long-held principle of exclusively defensive posture to a more practical military system. The possession of counterstrike capabilities is considered constitutional within the three conditions for the use of force recognized under Article 9 of the Constitution—when an armed attack is occurring or imminent, when there are no other means available, and when it is limited to the minimum necessary—but the interpretation of these conditions has been expanding year by year.

Personnel challenges are also serious. On April 9, the Ministry of Defense announced its policy to significantly increase the proportion of female Self-Defense Force personnel by the mid-2030s. Amidst a declining number of young applicants for Self-Defense Force enlistment due to an aging population and low birth rates, this initiative is positioned as a measure to secure human resources. Currently, the proportion of female Self-Defense Force personnel is about 7 percent, and the Ministry of Defense aims to significantly raise this figure to alleviate the severe personnel shortage.

The realization of Japan's counterstrike capabilities can be evaluated from the perspective of strengthening deterrence. However, their effectiveness is contingent upon multiple conditions. Delays in the introduction of Tomahawks, progress in the development of ship and air-launched variants, and, above all, the establishment of integrated operations are all under scrutiny. Considering the geopolitical vulnerabilities of the southwestern islands, ground-launched long-range missiles are quantitatively limited, and their combination with mobility deployment capabilities is essential. Additionally, there is a risk that the existence of counterstrike capabilities could accelerate a regional arms race. The missile capabilities of China and North Korea far exceed Japan in both quality and quantity, and careful analysis is needed to understand how Japan's deployment of long-range missiles will impact their military doctrines.

As Japan breaks free from the shell of its exclusive defense policy that has lasted for eighty years post-war, its trajectory holds the potential to reconstruct the security structure of East Asia itself. Cooperation with the United States, strategic dialogue with neighboring countries, and consistency in constitutional interpretation domestically—these three axes will require Japan's defense policy to navigate with both extreme caution and boldness in the future.