North Korea's New Missile Launch — Spiral

📡 THE SIGNAL — What Happened

Why it matters: North Korea's launch of a new long-range missile is not merely a provocation, but a structural turning point that will reshape the entire security architecture of East Asia. It could trigger an irreversible shift in Japan's defense policy from "shield" to "spear and shield."

• Military — North Korea conducted a test launch of a new long-range missile in January 2026, which landed in the Sea of Japan (East Sea).
• Diplomacy — Immediately after the launch, the Japanese government convened an emergency meeting of the National Security Council (NSC) to discuss its response.
• Alliance — Japan, the U.S., and South Korea began discussions on a joint response framework within 24 hours of the launch.
• Technology — This missile is believed to be a new type with improved range and accuracy compared to conventional models, and the possibility of solid-fuel propulsion has been pointed out.
• Defense — Based on the three security documents (Anpo San Bunsho) formulated at the end of 2022, Japan is accelerating the development of its counterstrike capabilities (enemy base attack capabilities).
• Budget — Japan's defense budget for fiscal year 2026 is expected to reach approximately 8 trillion yen, exceeding about 1.5% of GDP.
• Equipment — Japan is proceeding with the construction of two Aegis system-equipped vessels, aiming for their commissioning in fiscal year 2027.
• Sanctions — There are moves for additional sanctions resolutions in the UN Security Council, but the exercise of veto power by China and Russia is a concern.
• Nuclear Development — North Korea is estimated to possess 50-60 nuclear warheads as of 2025 and is continuing technological development for miniaturization and multiple warheads.
• Economy — Immediately after the test launch, the Nikkei 225 stock average temporarily fell by over 500 points, while defense-related stocks rose against the trend.
• Public Opinion — In a public opinion poll at the end of 2025, approximately 67% of Japanese citizens responded that they support strengthening defense capabilities, marking a record high.
• Technological Cooperation — Japan and the U.S. are accelerating the joint development of GPI (Glide Phase Interceptor), targeting deployment in 2028.

To understand North Korea's missile development and the changes in East Asia's security environment, it is necessary to take a panoramic view of the structural changes over the approximately 35 years since the end of the Cold War.

The First North Korean Nuclear Crisis in 1994 seemed to be temporarily contained by the U.S.-DPRK Agreed Framework. However, this agreement was merely a means for North Korea to buy time to continue its nuclear and missile development covertly. Since its first nuclear test in 2006, North Korea has conducted a total of six nuclear tests and dozens of missile launches, each time leading to strengthened UN sanctions, establishing a cycle of "provocation → sanctions → provocation." This cycle itself is a typical example of the "spiral of conflict" pattern.

For Japan's security policy, 2017 was a major turning point. North Korea successively conducted test launches of Hwasong-14 and Hwasong-15, and J-Alerts were issued for missiles passing over the Japanese archipelago. This shock instilled a deep sense of crisis in Japanese society, posing a fundamental question of how far it could respond within the framework of "exclusive defense."

In December 2022, the Kishida administration cabinet-approved the three security documents (National Security Strategy, National Defense Strategy, and Defense Buildup Program), achieving the largest transformation in Japan's post-war security policy. Explicitly stating the possession of counterstrike capabilities and setting a target to raise defense spending to 2% of GDP signified a decisive departure from the post-war defense doctrine of "devoting solely to a shield," which had been formed under the constraints of Article 9 of the Constitution.

However, this transformation is not solely due to the North Korean threat. China's rapid military buildup, particularly the rising tensions in the Taiwan Strait, the disruption of the international order due to Russia's invasion of Ukraine, and the increasing demands from the U.S. for burden-sharing from its allies are all interacting. North Korea's missile launch is acting as a "catalyst" to justify changes in Japan's defense policy amidst the confluence of these structural factors.

The answer to the question "Why now?" is multifaceted. First, there is North Korea's technological advancement. The acquisition of solid-fuel propulsion technology significantly shortens launch preparation time and dramatically enhances the capability for surprise attacks from mobile launchers. This could fundamentally overturn the premises of existing missile defense systems. Second, there are changes in the international environment since 2025. As the U.S. strategy against China becomes more acute, the North Korean issue is increasingly taking on the character of a dependent variable in the U.S.-China rivalry. By strategically reserving its exercise of influence over North Korea, China has effectively given North Korea a free hand. Third, there is the deepening of Russia-North Korea relations. Triggered by the war in Ukraine, military cooperation between the two countries has reached its highest level since the Cold War, and it is pointed out that North Korea may be receiving advanced technology from Russia.

For Japan, this situation is also a matter of "path dependency." The security system, which has relied on the U.S. "nuclear umbrella" for 80 years since the war, is extremely vulnerable to qualitative changes in U.S. engagement. The transactional approach to alliances demonstrated by the Trump administration (first and second terms) instilled deep anxiety within Japan's security community. The autonomous strengthening of defense capabilities is a structural response to this anxiety.

Furthermore, it is noteworthy that North Korea's missile launch is also influencing Japan's domestic political dynamics. Public support for increased defense spending is at a historically high level, which serves as political capital for the government to promote defense policy. The dynamic of "crisis opportunism," where crises enable reforms, underlies the transformation of Japan's defense policy.

The delta: North Korea's launch of a new missile is a technological escalation that, due to advancements in solid-fuel technology, shakes the premises of existing missile defense systems, acting as a catalyst for Japan to irreversibly shift its defense buildup based on the three security documents (Anpo San Bunsho) from "planning" to "execution."