North Korea's Missile Relaunch — A
North Korea's resumption of long-range missile launches in early 2026, with one passing over the Japanese archipelago, poses the greatest challenge to Japan's post-war exclusively defense-oriented policy. Calls for a defense policy review are surging on social media, particularly X, and the polarization of public opinion is accelerating the policy-making timeline.
── Understand in 3 points ─────────
- • North Korea conducted at least three long-range ballistic missile (ICBM-class) launches between January and March 2026, with one passing over the Japanese archipelago.
- • The launched missile is presumed to be an improved version of the Hwasong-18 (solid-fuel ICBM), making pre-detection difficult due to reduced launch preparation time.
- • The Japanese government is considering accelerating the deployment of counterstrike capabilities (stand-off missiles) based on the three security-related documents formulated in December 2022.
── NOW PATTERN ─────────
The "spiral of conflict," where North Korea's missile launches and Japan's defense buildup mutually justify each other, is accelerating. This simultaneously reveals pressure to break Japan's post-war security "path dependency" and "alliance strain" within the Japan-U.S.-South Korea alliance.
── Probabilities and Responses ──────
• Base case 55% — Frequency and types of North Korean missile launches, UN Security Council response, scale of Japan's supplementary budget, progress of THAAD deployment discussions.
• Bull case 15% — Signs of Chinese pressure on North Korea (oil supply data, diplomatic movements), reports of informal diplomatic channels, implementation of Japan-U.S.-South Korea BMD joint exercises.
• Bear case 30% — Success or failure of North Korea's MIRV demonstration test, signs of nuclear tests (tunnel activity at Punggye-ri), U.S. public opinion polls on the Japan-U.S. alliance, trends in resident movements around SDF bases.
📡 THE SIGNAL — What Happened
Why it matters: North Korea's resumption of long-range missile launches in early 2026, with one passing over the Japanese archipelago, poses the greatest challenge to Japan's post-war exclusively defense-oriented policy. Calls for a defense policy review are surging on social media, particularly X, and the polarization of public opinion is accelerating the policy-making timeline.
- Military — North Korea conducted at least three long-range ballistic missile (ICBM-class) launches between January and March 2026, with one passing over the Japanese archipelago.
- Military — The launched missile is presumed to be an improved version of the Hwasong-18 (solid-fuel ICBM), making pre-detection difficult due to reduced launch preparation time.
- Policy — The Japanese government is considering accelerating the deployment of counterstrike capabilities (stand-off missiles) based on the three security-related documents formulated in December 2022.
- Public Opinion — "#DefensePolicyReview" trended on X (formerly Twitter), dividing public opinion between proponents and opponents. An NHK poll showed support for increased defense spending rising to 58%.
- Diplomacy — The UN Security Council held an emergency meeting, but no new sanctions resolution was adopted due to opposition from China and Russia.
- Technology — Japan's Aegis system-equipped vessels (Maya-class and Atago-class) maintain an interception posture with SM-3 Block IIA, but have no record of successful interception in actual combat.
- Economy — Share prices of defense-related companies (Mitsubishi Heavy Industries, Kawasaki Heavy Industries, IHI) rose by an average of 12% in the week following the launch.
- Alliance — The U.S. military proposed additional deployment of THAAD (Terminal High Altitude Area Defense) systems at U.S. bases in Japan.
- Region — South Korea announced the strengthening of its deterrence with its own KSS-III missile submarines, creating a divergence in the Japan-U.S.-South Korea trilateral cooperation framework.
- Technology — North Korean missiles are suspected of being equipped with MIRV (Multiple Independently Targetable Reentry Vehicle) technology, raising questions about the effectiveness of conventional interception systems.
- Finance — The FY2026 defense budget is approximately 8.5 trillion yen (about 1.5% of GDP), but an additional 3 trillion yen is needed to reach the NATO standard of 2%.
- Society — Resident opposition movements continue in candidate sites for missile defense facilities, such as Okinawa and Akita prefectures, causing delays in deployment plans.
To understand the relationship between North Korea's missile development and Japan's security policy, it is necessary to survey the structural transformation of the East Asian security order after the end of the Cold War.
In 1993, North Korea launched its first Nodong missile into the Sea of Japan, shocking Japanese society. This marked the starting point for discussions on introducing missile defense (BMD) in Japan. At the time, within the framework of "exclusively defense-oriented policy," possessing enemy base attack capabilities was difficult even to discuss due to constitutional constraints. However, this initial Nodong launch became the starting point for the long road of Japan-U.S. joint research and development of missile defense systems.
In August 1998, North Korea launched the Taepodong-1, with its warhead passing over the Japanese archipelago and landing in the Pacific Ocean. This incident brought about a decisive shift in Japan's perception of security. The recognition that "the Sea of Japan is no longer a natural barrier" spread, and in 1999, Japan-U.S. joint BMD technology research officially began. Simultaneously, this crisis spurred the introduction of Japan's first intelligence-gathering satellites, marking the first step toward building its own surveillance capabilities.
Since 2006, North Korea has repeatedly conducted nuclear tests and missile launches, each time incrementally strengthening Japan's defense posture. Through the deployment of PAC-3 (2007), the addition of BMD capabilities to Aegis destroyers (2007-), and the launch of Hwasong-14 and Hwasong-15 ICBMs in 2017, Japan has built a multi-layered defense system using missile defense as a "shield." However, this "shield-only" approach had structural limitations: the asymmetry where the interceptor side requires a 100% success rate, while the attacker side can achieve its objective by breaking through even once.
The 2017 crisis was particularly severe. North Korea launched Hwasong-12 intermediate-range ballistic missiles twice on trajectories passing over Japan, triggering J-Alerts primarily in Hokkaido. The sight of residents being instructed to evacuate to concrete buildings was a reality post-war Japan had never experienced. During this period, discussions on "enemy base attack capabilities" intensified under the Abe administration, but the debate was shelved due to a temporary easing of tensions following the 2018 U.S.-North Korea summit.
In 2022, the international security environment drastically changed with the Ukraine war. In December of the same year, the Kishida administration revised the three security-related documents (National Security Strategy, National Defense Strategy, and Defense Buildup Program), formally deciding to possess "counterstrike capabilities." The goal of raising defense spending to 2% of GDP was also explicitly stated. This marked the biggest turning point in Japan's post-war security policy. Concrete "spear" capabilities were acquired, such as the decision to purchase 400 Tomahawk cruise missiles from the U.S. and the development of an extended-range version of the Type 12 Surface-to-Ship Missile.
However, with a temporary decrease in North Korean missile launches from 2023 to 2025, public interest in the urgency of strengthening defense capabilities had waned. Opposition to defense tax increases remained strong, and national discussions on specific operational scenarios for "counterstrike capabilities" did not sufficiently deepen.
The resumption of launches in early 2026 came precisely after this "period of calm." Several factors lie behind North Korea's renewed launches. First, the Kim Jong-un regime declared "qualitative improvement of nuclear forces" at the 2025 Party Congress and is rushing to demonstrate the reliability of MIRV technology and solid-fuel ICBMs. Second, U.S. political attention is dispersed across Ukraine, the Middle East, and the Taiwan Strait, reducing diplomatic pressure on North Korea. Third, strengthened relations with China and Russia have further diminished the effectiveness of UN sanctions, effectively bringing the cost of missile launches for North Korea close to zero.
Within this structural context, Japan faces the dual challenge of rapidly developing both a "shield" (missile defense) and a "spear" (counterstrike capability). Moreover, technologically, the difficulty of interception continues to rise due to North Korea's MIRV and maneuverable warhead capabilities, making the reality that "a perfect shield does not exist" increasingly clear. The polarization of public opinion on social media reflects society's anxiety and confusion regarding this structural dilemma.
The delta: North Korea's missile technology has undergone a qualitative transformation with solid-fuel and MIRV capabilities, fundamentally shaking the effectiveness of the conventional "detect → intercept" paradigm. Simultaneously, the immediacy and polarization of public opinion on social media are compressing the timeline for policy discussions, leaving Japan's security policy torn between "rapid transformation without sufficient debate" and "inaction due to an endless loop of discussions."
🔍 BETWEEN THE LINES — What the News Isn't Saying
The biggest point not conveyed by official reports is how pessimistic the Japanese government's internal assessment of the actual success rate of missile interception is. The 77% test success rate of SM-3 Block IIA is a figure under ideal conditions, and it could significantly decrease in a real combat environment when considering MIRV, decoys, and electronic jamming. The true reason Japan is rushing Tomahawk deployment is a cold military judgment: "the uncertainty of interception is too high, so there is no choice but to shift focus to deterrence that prevents launches (punitive deterrence)." In other words, counterstrike capability is not "an extension of exclusively defense-oriented policy" but a strategic necessity to complement the limitations of missile defense. However, the government avoids publicly admitting this true intention, as it would undermine trust in existing BMD systems.
NOW PATTERN
Spiral of Conflict × Path Dependency × Alliance Strain
The "spiral of conflict," where North Korea's missile launches and Japan's defense buildup mutually justify each other, is accelerating. This simultaneously reveals pressure to break Japan's post-war security "path dependency" and "alliance strain" within the Japan-U.S.-South Korea alliance.
Intersection of Dynamics
The three structural dynamics—"spiral of conflict," "path dependency," and "alliance strain"—are mutually reinforcing, complicating Japan's security environment.
As the spiral of conflict accelerates, pressure to depart from path dependency increases. Each time a North Korean missile passes over Japan, the perception that "an exclusively defense-oriented policy cannot protect the nation" spreads, and support for developing counterstrike capabilities rises. However, this rapid policy shift creates friction with the institutional accumulation (legal frameworks, organizational culture, civil society norms) cultivated over 80 years of path dependency. This friction leads to policy inconsistencies and implementation delays, resulting in a "deterrence gap."
This deterrence gap further deepens alliance strain. If Japan rapidly strengthens its independent defense capabilities, its reliance on U.S. extended deterrence will change, necessitating a readjustment of roles within the alliance. However, this readjustment will not proceed quickly. While the U.S. welcomes Japan's self-reliance, it is concerned that the integrity of command and control may be compromised. South Korea views Japan's military buildup with caution in a historical context. This internal discord within the alliance, when conveyed to North Korea, reduces the credibility of deterrence and invites further North Korean provocations—thus accelerating the spiral of conflict even more.
Furthermore, the speed of public opinion formation via social media is exerting a "time compression" effect on all three of these dynamics. Previously, security policies were incrementally changed after years of expert discussions. However, real-time public opinion formation on X demands immediate reactions from political leaders, making deliberate strategic judgments difficult. The immediacy of public opinion accelerates the spiral of conflict, prompts hasty departures from path dependency, and deprives the alliance of the diplomatic time needed for delicate adjustments. The current situation, where these three dynamics operate simultaneously and mutually amplify each other, can be described as the most structurally complex and dangerous phase for Japan's post-war security.
📚 PATTERN HISTORY
1998: Taepodong-1 Passes Over the Japanese Archipelago
A pattern where external shocks incrementally transform Japan's defense policy. After the Taepodong shock, joint BMD research began, and the introduction of intelligence-gathering satellites was decided.
Structural similarities with the present: Shifts in Japan's security policy are always driven by external shocks. However, the "window of reform" after a shock is often short, and comprehensive policy changes rarely occur.
2006: North Korea's First Nuclear Test and UN Security Council Resolution 1718
A pattern where international sanctions fail to alter North Korea's behavior. Sanctions were repeatedly strengthened, but nuclear and missile development continued to accelerate.
Structural similarities with the present: Sanctions alone cannot prevent the transition to a nuclear-armed state. Sanctions without cooperation from China and Russia lack effectiveness, and the cost of launches for North Korea continues to decrease.
2017: Consecutive Launches of Hwasong-12, -14, and -15, and the Peak of U.S.-North Korea Tensions
A pattern where "maximum pressure" and "fire and fury" are followed by sudden summit diplomacy. The escalation of the crisis abruptly shifted to dialogue.
Structural similarities with the present: Increased military tension can sometimes lead to diplomatic breakthroughs, but such diplomatic achievements are not sustained. The 2018-19 U.S.-North Korea negotiations did not yield concrete denuclearization results.
2022: Russia's Invasion of Ukraine and Revision of the Three Security-Related Documents
A pattern where a distant war indirectly transforms Japan's security policy. The lessons from Ukraine strengthened public opinion that "one's own country must be defended by oneself," justifying the possession of counterstrike capabilities.
Structural similarities with the present: Not only direct threats but also shifts in the international order act as catalysts for Japan's policy changes. However, there is a significant time lag between policy decisions and actual capability building.
1983: Korean Air Flight 007 Shootdown Incident and the Cold War's "Spiral of Conflict"
A pattern where an accidental incident accelerates the spiral of conflict. This incident temporarily exacerbated U.S.-Soviet tensions to an extreme degree but ultimately also served as a prelude to the Reagan-Gorbachev dialogue.
Structural similarities with the present: Even within a spiral of conflict, the risk of accidental incidents is the greatest danger. The possibility of missile passage over the Sea of Japan and the Pacific Ocean causing misidentification or accidental clashes always exists.
Patterns Revealed by History
Historical patterns indicate a structural characteristic: North Korea's missile crises have repeatedly transformed Japan's security policy "incrementally," but these transformations have always been "reactive" rather than "proactive." The 1998 Taepodong shock, the 2006 nuclear test, the 2017 ICBM crisis, the 2022 Ukraine war—all opened "windows of reform" through external shocks, but these windows closed relatively quickly, failing to lead to comprehensive strategic reorganization.
Another important pattern is the gradual neutralization of international sanctions. Since 2006, six UN sanctions resolutions have failed to halt North Korea's nuclear and missile development. This is not a problem with the design of the sanctions but a structural issue where China and Russia, two permanent members of the Security Council, find strategic interests in maintaining the North Korean regime. As of 2026, this structure is even more entrenched than it was in 2006.
History strongly suggests that this pattern is likely to repeat this time. Shock → policy change discussions → partial reforms → easing of tensions → reform stagnation—to break this cycle, an autonomous construction of a structural security strategy is needed, rather than merely "reacting" to external shocks. However, this means consciously overcoming 80 years of path dependency, which is the most difficult challenge for Japan's political system.
🔮 NEXT SCENARIOS
North Korea will conduct an additional 3 to 5 missile launches in 2026, with at least one being ICBM-class on a trajectory passing over Japan. The Japanese government will issue J-Alerts, and the SDF will assume an interception posture with SM-3, but actual interception will not be carried out (as the trajectory will not indicate impact on Japanese territory). The UN Security Council will issue a statement, but no new sanctions resolution will be adopted due to opposition from China and Russia.
Domestically in Japan, discussions on increasing defense spending and accelerating the deployment of counterstrike capabilities will intensify, leading to additional defense-related appropriations (500 billion to 1 trillion yen) in the FY2026 supplementary budget. The deployment of Tomahawk cruise missiles will be brought forward, with the first batch deployed by the end of 2026. However, the extended-range version of the Type 12 Surface-to-Ship Missile will maintain its development and production timeline, with deployment planned for 2028 or later.
Public opinion will temporarily lean towards defense strengthening, but once concrete tax increase discussions begin, backlash will emerge, causing government approval ratings to fluctuate wildly. Public opinion on X will remain polarized, with ideological conflicts overshadowing constructive policy debates. The U.S. will achieve additional THAAD deployments, but coordination with local communities regarding site selection in Japan will face difficulties. Japan-U.S.-South Korea trilateral cooperation will be formally maintained, but practical operational integration will have limitations. North Korea's MIRV technology will not yet reach a practical stage, and single-warhead ICBMs will remain the main force for the time being, so the effectiveness of existing missile defense systems will not be completely negated.
Implications for Investment/Action: Frequency and types of North Korean missile launches, UN Security Council response, scale of Japan's supplementary budget, progress of THAAD deployment discussions.
North Korea's missile launches will have a greater-than-expected impact on the international community, leading China to increase pressure on North Korea. The Xi Jinping administration will judge that North Korea's MIRV development also negatively affects China's own security (as it would lead to a significant Japanese military buildup) and will exert substantial pressure, including restrictions on oil supply. This will cause North Korea to temporarily halt launches, and dialogue through informal diplomatic channels will begin.
In Japan, in response to this diplomatic progress, a "two-front strategy" pursuing both defense strengthening and diplomatic solutions will gain national consensus. A phased roadmap towards achieving 2% of GDP for defense spending will be formulated through bipartisan agreement, and constructive parliamentary discussions on specific operational guidelines for counterstrike capabilities will advance. The SDF's missile defense capabilities will be systematically strengthened, demonstrating a high interception rate in Japan-U.S. joint BMD live-fire exercises by the end of 2026.
Japan-U.S.-South Korea trilateral cooperation will deepen, and a real-time missile warning data sharing system will be established. South Korea will also choose a cooperative path over an independent one, accelerating the construction of a multi-layered regional missile defense network. In this optimistic scenario, North Korea's missile crisis functions as a "constructive external shock," simultaneously achieving a qualitative improvement in Japan's security posture and strengthening regional cooperation frameworks. However, it will not lead to North Korea's denuclearization, and the parallel pursuit of deterrence and dialogue will remain a long-term challenge.
Implications for Investment/Action: Signs of Chinese pressure on North Korea (oil supply data, diplomatic movements), reports of informal diplomatic channels, implementation of Japan-U.S.-South Korea BMD joint exercises.
North Korea successfully demonstrates MIRV technology and conducts a multi-warhead ICBM launch test in 2026. This fundamentally calls into question the effectiveness of Japan's existing missile defense systems. Additionally, North Korea hints at an atmospheric nuclear test over the Pacific Ocean (an act breaking a taboo since the 1960s), pushing regional tensions to their worst level since the Cold War.
Domestically in Japan, the division of public opinion will deepen further. Proponents of defense strengthening will expand discussions to include nuclear sharing and independent nuclear armament, intensifying conflict with constitutional pacifists. Social divisions will be amplified on social media, and resident movements at planned defense facility construction sites may escalate into violent clashes. The government will be caught between public opinions, and time will pass without decisive policies being enacted.
In the U.S., amidst the political climate leading up to the presidential election, domestic debate over involvement in Japan's defense will reignite. Rhetoric such as "Why should young Americans risk their lives for Japan?" will gain traction, reducing the credibility of extended deterrence. As fissures in the Japan-U.S. alliance become visible, North Korea will undertake even bolder actions.
In the worst-case scenario, the risk of accidental incidents increases. Missile launches over the Sea of Japan and SDF/U.S. military alert activities could occur in close proximity, potentially leading to unintended escalation due to misidentification or communication failures. In this pessimistic scenario, the spiral of conflict becomes uncontrollable, and the entire region falls into a vicious cycle of arms race and instability.
Implications for Investment/Action: Success or failure of North Korea's MIRV demonstration test, signs of nuclear tests (tunnel activity at Punggye-ri), U.S. public opinion polls on the Japan-U.S. alliance, trends in resident movements around SDF bases.
Key Triggers to Watch
- North Korea's next ICBM-class missile launch (especially if it includes MIRV technology demonstration): April-June 2026 (high probability of launch around Kim Il-sung's birthday on April 15 and Korean People's Army Foundation Day on April 25).
- UN Security Council vote on a sanctions resolution and China/Russia's response: Within 1-2 weeks after the next missile launch.
- Decision by the Japanese government on additional defense-related appropriations in the FY2026 supplementary budget: During the ordinary Diet session from May to July 2026.
- Decision and announcement of additional THAAD system deployment sites in Japan by the U.S. military: Second half of 2026 (including local coordination with candidate sites).
- Joint statement on missile defense cooperation at Japan-U.S.-South Korea summit or foreign ministers' meeting: Around the 2026 G7 Summit (scheduled for June).
🔄 TRACKING LOOP
Next Trigger: North Korea's next missile launch (most likely around Kim Il-sung's birthday on April 15, 2026) — The presence or absence of MIRV technology will decisively influence the future direction of Japan's defense policy.
Continuation of this pattern: Tracking Theme: North Korea Missile Escalation Cycle — The next milestones are launch trends around Kim Il-sung's birthday in April 2026 and the UN Security Council's response.
>How do you read it? Participate in Prediction →
