The Deployment of Japan's Ground Self-Defense Force Type 25 Missiles Moves the 1000-Kilometer Deterrence Network

The author felt a significant sense of discomfort at the mention of the names of the Kengun and Fuji garrisons as missile deployment sites. If the discussion were about the southwestern islands, readers would likely think of Miyako, Ishigaki, and Yonaguni. However, the deployment of the Type 25 anti-ship guided missile and Type 25 high-speed glide projectile, commonly referred to as HVGP, reported by Army Recognition on July 7, is not a simple matter of placing weapons on the islands to achieve deterrence.

According to the report, the Japan Ground Self-Defense Force announced on March 31 that it had introduced the improved Type 12 anti-ship guided missile as the Type 25 anti-ship guided missile and the high-speed glide projectile as the Type 25 HVGP into operational units. The range of the improved Type 12 has been extended from approximately 200 kilometers to about 1000 kilometers with some configurations, and future HVGPs are being considered for ranges of around 2000 kilometers.

The Map Changed by a 1000-Kilometer Range

The figure of 1000 kilometers looks very appealing on a map. From Kyushu, it can reach a wide area of the East China Sea, and from the southwestern islands, it is easy to discuss its impact on the waters around Taiwan. The launchers are said to be mounted on 8-wheeled vehicles and carry 8 canisters, making them compatible with the Ground Self-Defense Force's operational concept of mobility, firing, and maneuvering.

However, based on my experience in maritime operations, the most challenging aspect of long-range missiles is not the distance. It is about who will identify moving vessels, at what point, and with what accuracy. Unless coastal radars, P-1 patrol aircraft, drones, satellites, and the U.S. military's information network are connected into a single operational picture, the 1000-kilometer range will remain just a political headline.

Institutionalizing Counterattack Capability Rather Than Extending the Type 12

The Type 25 anti-ship guided missile can be described as an advanced version of the Type 12 in terms of its appearance. The elements of low-altitude cruising, stealthy design, inertial navigation and satellite positioning, terminal phase radar guidance, and mid-course guidance via data link represent a natural evolution for modern anti-ship missiles.

However, the policy implications are more significant than merely extending the range. The 2022 National Security Strategy explicitly states the need to possess counterattack capabilities to target the enemy's missile launch means. The deployment of the Type 25 indicates that we have entered a phase of translating that language into units, ammunition depots, communication facilities, and training plans. For the first time, legal concepts become logistical burdens.

Counterattack capability does not arise the moment a missile is purchased. It only functions when target information, ammunition resupply, and political decisions move at the same speed.

What HVGP Aims For

The HVGP has a different character than cruise missiles. After being accelerated by a rocket, it is said to glide at high speed while performing erratic maneuvers, leaving little time for the intercepting side. The anticipated targets include landing forces, command posts, runways, and potentially high-value moving targets.

This connects to the idea of preventing enemy landing forces from approaching the islands in the defense of the southwestern islands. During the Cold War, the Japan Maritime Self-Defense Force emphasized anti-submarine lines to prevent Soviet submarines from entering Japanese waters. Today, Japan is trying to increase the cost of utilizing the maritime area with long-range firepower launched from the ground, in addition to anti-submarine lines.

Role Sharing Within the Japan-U.S. Alliance

With the acquisition of U.S. Tomahawks, the Joint Strike Missile for the F-35, and the Ground Self-Defense Force's Type 25, Japan's strike capabilities appear to be rapidly strengthening. Furthermore, if mid-range firepower like the U.S. Army's Typhon enters exercises around Japan, multiple launch platforms will emerge inside the first island chain.

However, there are pitfalls here as well. As the number of missiles possessed by Japan increases, the coordination of target selection, rules of engagement, and information sharing with the U.S. military becomes more complex. Particularly in the East China Sea, the Chinese Navy, Coast Guard, militia, and merchant vessels coexist in the same waters. To avoid misidentification, the accuracy of the decision not to fire is more critical than the ability to fire.

Operational Constraints of the Local Community

The mention of mainland garrisons like Kengun and Fuji as deployment sites raises issues of resident explanations and base protection. As missiles become long-range, the target value from the adversary's perspective also increases. How to secure the protection of ammunition depots, communication facilities, transport routes, and ports is a part that is difficult to reflect in equipment tables but is likely to break down first in actual combat.

In my view, the essence of the Type 25 is not that "Japan can strike 1000 kilometers away." It is that Japan has entered an era where it must politically decide whether to strike 1000 kilometers away within a few minutes to tens of minutes. There lies a precariousness that has not yet been sufficiently discussed.

Sources: Army Recognition, Japan Ground Self-Defense Force statement cited by Army Recognition, Japan National Security Strategy 2022.