A Historical Shift in Japan's Security Policy: The Abolition of the "Five Types" of the Three Principles on Transfer of Defense Equipment and the Expansion of North Korean Missile Threats

On April 21, 2026, the Takai Cabinet revised the "Three Principles on Transfer of Defense Equipment" and its operational guidelines during the National Security Council and Cabinet meetings, abolishing the previous regulations that limited the overseas transfer of defense equipment to five categories: "rescue," "transport," "alert," "surveillance," and "mine sweeping." With this revision, the overseas transfer of "weapons" with lethal and destructive capabilities, such as fighter jets, missiles, and ships, has become generally possible. It can be said that the historical framework that has strictly limited arms exports in Japan's post-war security policy has been fundamentally rewritten.

The background of this revision lies in the rapid deterioration of the security environment in the East Asian region. Since the establishment of the Three Principles on Transfer of Defense Equipment under the Abe administration in 2014, the government has gradually expanded the scope of transfers, but the constraint of the "five categories" has always existed. However, following the new national security strategy, defense capability development plan, and mid-term defense capability development plan, collectively referred to as the "Three Security Documents," which were formulated in December 2022 and explicitly called for a fundamental review of defense equipment transfers, the government reached this revision after adjustments within the ruling party. Prime Minister Takai stated at a press conference, "To ensure the peace and security of our country and the international community, it is necessary to adapt the way of defense equipment transfer to the times," emphasizing the validity of the revision.

The core change of the revision is the expansion of the scope of transfer review. Until now, the five categories functioned as "examples of permissible equipment," making the transfer of other equipment virtually impossible. The new operational guidelines abolish this constraint, allowing all defense equipment, including weapons with lethal capabilities, to be eligible for transfer. However, a review process that comprehensively assesses the appropriateness of the purpose, the situation of the transfer destination, and the impact on Japan's security is maintained, meaning that unlimited exports will not be immediately possible. While the opposition has criticized this as a "de facto lifting of the arms export ban," the ruling party counters that "proper management is ensured through strict review procedures."

This revision will have a significant impact on Japan's defense industry. For many years, Japan's defense industry has relied solely on domestic demand, making it difficult to reduce costs through mass production, and it has lagged behind defense companies in Europe, the United States, and Israel in terms of international competitiveness. With the principle of arms transfer now possible, major defense companies such as Mitsubishi Heavy Industries, Kawasaki Heavy Industries, and IHI are expected to enter overseas markets for fighter jets, ships, and missile-related equipment. The path has also been opened for the export of completed aircraft to third countries for the next-generation fighter GCAP (Global Combat Air Program), which Japan is jointly developing with Italy and the UK, significantly enhancing the project's economic viability.

On the other hand, North Korea's missile launch experiments occurring during this period are also a serious concern. On April 19, multiple ballistic missiles were launched from near North Korea's east coast around 6 a.m. According to the Ministry of Defense, the missiles have already fallen, and the landing site was outside Japan's exclusive economic zone. The three countries of Japan, the United States, and South Korea immediately began close coordination and are conducting detailed analyses of the missile types and flight distances. North Korea has been accelerating the development of solid-fuel ICBMs since 2025 and announced in February that it had conducted a launch experiment of the "Hwasong-19" type. The improvement of ballistic missile technology continues to exert direct pressure on Japan's missile defense system.

The Self-Defense Forces are strengthening missile defense, and the 2026 budget includes funding for the construction of Aegis-equipped ships, as well as subsidies for the development of underground command centers in Okinawa Prefecture and the Sakishima Islands. The enhancement of defense capabilities in the southwestern islands is positioned as a core deterrent against China's maritime expansion, and in addition to the ground-to-air and ground-to-ship missile units deployed on Yonaguni Island, Ishigaki Island, and Miyako Island, the establishment of electronic warfare units is also underway.

Furthermore, Japan's international defense cooperation is being developed in multiple dimensions. From April 20 to 24, the Self-Defense Forces are participating in NATO's cyber defense exercise "Locked Shields 2026." This not only enhances Japan's cyber defense capabilities but also symbolizes the deepening of cooperative relations with NATO. Additionally, on April 18, it was announced that Australia had signed a contract for the introduction of jointly developed vessels with Japan, which Defense Minister Koizumi welcomed in a statement. Japan and Australia are promoting joint development and production of defense equipment based on the security cooperation declaration of 2022, and this contract signing can be seen as a concrete outcome of that effort.

The revision of the Three Principles on Transfer of Defense Equipment holds the potential to transform not only domestic policy but also the security environment in East Asia itself. Japan's emergence as an arms-exporting country could serve as an opportunity to deepen defense industrial cooperation with the United States, a key ally, while also potentially introducing new friction in relations with China, Russia, and North Korea. The Chinese government has already expressed caution regarding this revision, labeling it as a "move towards Japan's militarization," and future diplomatic developments will be closely watched.

After 81 years since the end of World War II, Japan is being forced to make a historical choice between the ideal of being a "peaceful nation" and the demands of "realistic security." The revision of the Three Principles on Transfer of Defense Equipment is the most concrete manifestation of that choice and holds extremely important significance in forecasting the future of Japan's security policy. How the Takai Cabinet explains this policy shift to the public and maintains trust from the international community will be the biggest challenge moving forward.