Japan's Expansion of Ground Attack Capabilities and the Alliance Strategy Wavering Between US-China Rivalry

In March 2026, under strict security at the Kumamoto Prefecture Kengun Garrison, the Japan Ground Self-Defense Force deployed the improved version of the Type 12 Surface-to-Ship Guided Missile launch system. For the first time since the end of World War II, Japan has operationally deployed an offensive weapon with a range that far exceeds its own territory. This move symbolizes a fundamental turning point in Japan's post-war security policy.

The improved Type 12 Surface-to-Ship Guided Missile is a state-of-the-art cruise missile system developed by Mitsubishi Heavy Industries. The range of the initial model, introduced in 2015, was approximately 200 kilometers, but the improved version has extended its range to nearly 1,000 kilometers by replacing the engine with a turbofan. This capability means that if launched from the southwestern islands, major military facilities along the Chinese coast and strategic bases in North Korea will fall within range.

Stealth performance has also been significantly enhanced. The surface of the missile adopts an angular shape to minimize radar cross-section. By flying close to the sea surface, it is designed to make detection and interception by enemy air defense systems difficult. The Japanese government has allocated approximately 177 billion yen (about 1.13 billion dollars) for the procurement of this system, and the defense budget for fiscal year 2026 has reached a record high of about 9 trillion yen.

By around 2027, ship-launched and aircraft-mounted versions are also expected to be operationally deployed, with plans for integration into the domestically produced F-2 fighter jet. Furthermore, the construction of a new reconnaissance satellite network that provides real-time target information is being advanced in parallel, aiming for an integrated enhancement of intelligence, surveillance, and reconnaissance (ISR) capabilities.

The background to this capability expansion is the national security strategy revised in 2022. This document formally introduced the concept of "counterstrike capability," allowing for the attack of enemy military bases abroad if an attack is imminent or has already begun. This fundamentally changes the traditional division of roles in the Japan-U.S. alliance—Japan as the "shield" and the U.S. as the "spear."

Prime Minister Sanae Takichi visited Washington on March 17 for a summit meeting with President Trump. The Takichi administration achieved a landslide victory in the February 2026 general election, the first for the Liberal Democratic Party in 70 years, and has seen an increase in favorable evaluations from President Trump. Japan has promised a strategic investment fund of 550 billion dollars as part of a trade agreement with the U.S., and has already announced projects totaling 36 billion dollars, including a natural gas power plant for AI in Ohio, a deep-sea oil export facility in Texas, and a synthetic industrial diamond factory in Georgia.

During this summit, an additional investment project worth 100 billion dollars is expected to be announced, likely including copper refining, LCD display manufacturing, and nuclear power plant construction. In terms of defense, deeper information sharing and joint missile production are expected to be agreed upon, and Japan is likely to express its intention to participate in the "Golden Dome" missile defense initiative.

However, unexpected obstacles lie ahead for the deepening of the alliance. Although the Supreme Court ruled the tariff measures of the Trump administration under the International Emergency Economic Powers Act unconstitutional, the automobile tariffs under Section 232 of the Trade Act remain in effect, continuing to exert pressure on the Japanese economy. Furthermore, on March 11, the U.S. Trade Representative (USTR) initiated two Section 301 investigations regarding industrial overcapacity and the import of products made with forced labor, with Japan included as a subject of investigation.

In terms of energy security, a more serious crisis is looming. Military operations initiated by the Trump administration against Iran have led to the blockade of the Strait of Hormuz, cutting off a significant portion of Japan's oil imports. The Japanese government has ordered the largest-ever release of strategic oil reserves, but with no prospects for normalizing maritime transport routes, the effectiveness of this measure is limited. President Trump has suddenly demanded the dispatch of vessels to open the Strait of Hormuz from several allied countries, including Japan. There is also a high possibility that requests for mine-clearing support will follow.

Moreover, a concerning development is the transfer of U.S. military resources from Asia to the Middle East. Approximately 2,500 Marines and an amphibious assault ship stationed in Okinawa have been repurposed to the Arabian Sea, and the THAAD missile defense system has also been moved to the Middle East. While maintaining deterrence in the Taiwan Strait is an urgent issue, U.S. military strength in the Indo-Pacific region has significantly declined.

China has strongly opposed Japan's capability expansion. In response to Prime Minister Takichi's statement that "a crisis in Taiwan could constitute a situation threatening Japan's existence," Beijing has intensified economic pressure and tightened export controls on dual-use materials essential to advanced defense industries. The activities of the Chinese Navy have also become more active around Iwo Jima and the southwestern islands, emphasizing the strategic importance of these waters in the western Pacific.

On the other hand, the improved Type 12 missile is generating regional ripple effects. With Japan easing its defense equipment export regulations, the system can now be transferred to reliable partner countries. Australia is considering the introduction of this system as a complement or alternative to U.S.-made missile programs, with a price of about 3 million dollars per missile and a long range seen as advantageous for defending vast maritime approaches.

Interest is also rising in Southeast Asia. The Philippines and Vietnam have shown interest through Japan's Official Security Assistance (OSA) framework. For Manila, the deployment around the Luzon Strait would significantly enhance the defense of a crucial maritime corridor connecting the Pacific and the South China Sea. If multiple countries introduce the system simultaneously, it could form a "regional missile network" capable of information sharing and target coordination, significantly raising the strategic costs of any maritime aggression.

Prime Minister Takichi's visit to Washington will serve as a litmus test for balancing Japan's strategic autonomy and alliance relations. Faced with the triple challenges of trade friction, energy crises, and the declining presence of U.S. forces in the Indo-Pacific, Japan is being forced to navigate the difficult task of strengthening its own military capabilities while maintaining cooperative relations with the U.S.

The deployment of the improved Type 12 Surface-to-Ship Guided Missile symbolizes Japan's transition from a strictly defensive posture to proactive deterrence. This change has the potential to reshape the strategic balance in the Indo-Pacific for decades to come. However, its success hinges on how well Japan can harmonize its obligations as an ally with its own strategic interests.