In the security environment surrounding Japan, China’s military buildup and attempts to change the status quo in the region might be the most significant change in the nine years since the enactment of the former National Security Strategy (NSS). In particular, the rising military tension in the Taiwan Strait has reminded the Japanese government of the possibility of being forced to respond to a conflict in the Taiwan Strait.

According to various Japanese media reports, how exactly the Chinese threat should be described was one of the points of contention in the revision process of the strategy. China’s external stance in the former strategy was expressed as “an issue of concern for the international community.” Since the situation across the Taiwan Strait was stable then, it was described as “[containing] both orientations towards stability and potential instability.” The new NSS describes China as “a matter of serious concern” and “the greatest strategic challenge.” Of the situation across the Taiwan Strait, it states, “concerns are mounting rapidly, not only in the Indo-Pacific region including Japan, but also in the entire international community.” However, the use of the term “threat” to describe China, which was discussed during the revision process, was omitted. The new NSS also emphasizes confidence-building and enhanced communication with China. It should be noted that the new NSS clearly states that there has been no change in Japan’s position on relations with Taiwan since the 1972 Japan-China Joint Statement.

Counterstrike Capability in the New NSS

The new NSS calls for the possession of a counterstrike capability by the Self-Defense Forces (SDF) in view of China’s attempts to change the status quo in the region and North Korea’s nuclear and missile threats. This is a significant shift in Japan’s postwar security policy. Under the Constitution, Japan’s security policy has been based on an exclusively defense-oriented policy, which states that Japan will use its defensive capabilities only when the three conditions for the use of force are fulfilled. The three conditions were redefined in the 2015 Legislation for Peace and Security:

1. “When an armed attack against Japan has occurred, or when an armed attack against a foreign country that is in a close relationship with Japan occurs and as a result threatens Japan’s survival and poses a clear danger to fundamentally overturn people’s right to life, liberty and pursuit of happiness;
2. When there is no appropriate means available to repel the attack and ensure Japan’s survival and protect its people;
3. Use of force to the minimum extent necessary.”

Although the Japanese government considers possessing a counterstrike capability constitutional, it has put off acquiring the capability due to political consideration for domestic public opinion and the impact Japan’s remilitarization may have on neighboring countries.

According to the new NSS, the counterstrike capability is to be invoked “in cases where an armed attack against Japan has occurred, and as part of that attack ballistic missiles and other means have been used.” In other words, the government assumes that changes in the strategic environment have necessitated a counterstrike capability as the “minimum necessary force for self-defense” and that there has been no change in the existing exclusively defense-oriented policy. The new strategy also clearly states that the operation of such a capability is premised on the Japan-U.S. Security Treaty regime, focuses on strengthening deterrence, and cannot be developed into a preemptive attack.

The new strategy defines counterstrike capabilities as “the SDF capabilities that leverage stand-off defense capabilities and other capabilities” that enable the launch of an effective counterattack against the opponent’s territory. Specifically, such capabilities include the Type 12 Surface-to-Ship Missiles, the Island Defense High-Speed Gliding Missiles, the long-range Hypersonic Guided Missile, the Joint Strike Missiles on the F-35, the Joint Air to Surface Stand-Off Missiles on the F-15, and the newly introduced BGM-109 Tomahawk Missiles. In other words, the SDF mainly plans to enhance its long-range missile force, which it has already introduced.

As the primary deployment site for counterstrike capabilities, the new strategy calls for developing a defense structure for the Southwest Islands, a group of islands connecting Kyushu to Taiwan. The Defense Buildup Program, enacted in response to the new NSS, states that the Ground SDF’s 15th Brigade, based in Okinawa Prefecture, will be upgraded to a “division” and that the mobility of other units will also be enhanced. The plan also includes a policy to form a new unit equipped with long-range missiles. Furthermore, the plan contemplates deploying a supply base in the Southwest Islands to strengthen sustainability and resilience, where the SDF will place ammunition, fuel, and materials.

Tensions Near Japan’s Southwest Islands

In the Southwest Islands area, China’s public vessels have become a regular feature of activities in the waters surrounding the Senkaku Islands. Chinese military demonstrations or training around Taiwan have become more active. In addition, Chinese intermediate-range ballistic missiles landed within Japan’s exclusive economic zone when the PLA conducted a large exercise against Taiwan in August 2022. As a result, the Japanese public is now widely aware of the need to enhance defense capabilities and Japan’s role in the alliance with the U.S., perceiving China as a threat, especially in the Senkaku Islands or the Taiwan Strait.

In the event of a conflict in this area, there are three major patterns of possible Japanese responses. The first is a direct military conflict between Japan and China over the Senkaku Islands or a Chinese military invasion of Taiwan that involves an attack on Japanese territory, in which case Japan would consider counterattacking China as a matter of individual self-defense. The second is a case in which China’s military invasion of Taiwan does not involve an attack on Japan’s territory. Still, the Japanese government would recognize the situation as an “existential crisis” and exercise its right of collective self-defense to use force. The third is a case in which the government identifies China’s military invasion of Taiwan, which similarly does not involve an attack on Japanese territory, as a “critical influence situation,” and the SDF is allowed to provide logistical support to U.S. forces within a scope that does not involve the use of force.

Thus, the new NSS has not expanded the scope or interpretation of Japan’s right to exercise self-defense since the 2015 Legislation for Peace and Security. However, Japan’s counterstrike capability has increased the cost of China conducting military operations against Taiwan in a way that would activate Japan’s right of self-defense, including collective self-defense. In this regard, some domestic discussions have pointed out that there are still challenges for the Japanese government, the Ministry of Defense, and the SDF to respond to the above scenarios. In the past few years, several Taiwan contingency simulations have been conducted in Japan, which have pointed to numerous problems in the government’s recognition of what is happening in the Taiwan Strait. They also identify many challenges in developing the SDF’s counterstrike theory and practice.

A Sense of Crisis

Japan’s reason for announcing such a new strategy is nothing less than a sense of crisis regarding the current situation in the region. While building the defense system indicated in the new strategy, the Japanese government needs diplomatic efforts to appeal to China and other neighboring countries about its sense of crisis and the importance of dialogue and confidence building in the region.

Madoka Fukuda, Ph.D., is a Professor in the Department of Global Politics in the Faculty of Law of Hosei University in Japan. Updated 3/1/23.