The Launch of Two Short-Range Ballistic Missiles by North Korea Questions the Sustainability of Japan-U.S.-South Korea BMD
Tanaka TakashiNorth Korea's Launch of Two Short-Range Ballistic Missiles Questions the Sustainability of Japan-U.S.-South Korea BMD
On September 20, North Korea launched two short-range ballistic missiles (SRBMs) toward the eastern coast. According to reports from Reuters, CNN, and Japan Times based on announcements from the South Korean military, this marks the second launch within about a week. Details such as flight distance and altitude have not been sufficiently disclosed by the respective authorities, and there is currently no evidence to definitively classify these as new missiles.
The Rhythm of Launches Indicated by Numbers
Looking solely at these two launches, it may appear that North Korea has chosen a limited show of force. However, approximately ten short-range ballistic missile launches were reported in August, suggesting that this is more of a repetitive action combining training and political signaling rather than a single test. The weight of the warhead, the presence of terminal maneuvers, and the launch preparation time remain unconfirmed. This lack of information highlights the temporal challenges that Japan, the U.S., and South Korea face in ISR (Intelligence, Surveillance, and Reconnaissance).
The Role Required of the Japan Maritime Self-Defense Force
North Korea's SRBMs are weapons that not only directly threaten the Japanese mainland but also simultaneously make U.S. and South Korean forces operating around the Korean Peninsula and Japanese bases aware of their presence. The Aegis destroyers of the Japan Maritime Self-Defense Force serve as a connection point for information sharing with the U.S. Navy and ballistic missile defense (BMD). However, possessing the capability to respond to two missiles and being able to handle a situation where launches occur in succession from multiple directions are separate issues. The stockpile of interceptors, the operational availability of vessels, and crew rotation plans become as important as the performance of the equipment itself.
The Gap Between Exercises and Real Combat
The official announcements from the Japan Maritime Self-Defense Force record bilateral training with the U.S. in September and multilateral training involving Japan, the U.S., Australia, and South Korea. The recent launches reported by Reuters and CNN indicate that such cooperation must operate not merely as procedural exercises but within a short warning time. The weakness of trilateral cooperation lies not in detection capabilities but in who confirms the detection information at what point and transitions to interception decisions. There is also variability in the granularity of information released by Japan's Ministry of Defense with each launch, making the balance between public explanation and operational secrecy challenging.
Insights from Takashi Tanaka
For North Korea, the cost of launching short-range missiles is easier to manage compared to testing strategic weapons. On the other hand, the Japan-U.S.-South Korea side places naval vessels, aircraft, and communication networks in a high state of tension with each launch. This asymmetry cannot be resolved merely by increasing the number of interceptors. What is needed is a shift in focus from the idea of intercepting everything to sharing signs of launches, prioritizing critical targets, and continuing operations based on the assumption of attrition. The true blind spot is not the range of the missiles but whether the political decision-making and naval operations of Japan, the U.S., and South Korea can maintain the same pace in the event of consecutive launches over several days.
Main Sources
North Korea launched two short-range ballistic missiles towards the East Coast on September 20, 2026. This marks the second missile launch within a week, raising concerns about the effectiveness of the Japan-U.S.-South Korea missile defense systems. The details regarding the missiles' range and altitude remain undisclosed, highlighting challenges in intelligence and surveillance capabilities.
- North Korea launched two short-range ballistic missiles on September 20, 2026.
- This was the second missile launch in a week.
- The missiles were launched towards the East Coast of North Korea.
- Details on missile range and altitude were not disclosed.
- The launch raises concerns about the effectiveness of Japan-U.S.-South Korea missile defense systems.