Toplines

North Korea is likely developing a makeshift long-range strike complex that is increasingly integrating various munitions and systems. This strike complex may improve North Korea’s ability to penetrate South Korea’s integrated air and missile defense (IAMD) network. North Korea conducted a major missile and drone exercise on September 12.[1] The test consisted of tactical erector launcher (TEL)-fired Hwasong-11 short-range ballistic missiles (SRBM), 600mm multiple launch rocket systems (MLRS), cruise missiles, and two types of drones.[2] North Korean state media reported that the exercise aimed to improve North Korea’s integrated fire command system and practice using automated fire command across multiple platforms.[3] The September 12 exercise marked the first time North Korea used four different types of munitions — SRBM, MLRS, cruise missiles, and drones — in a single strike exercise.[4]

The September 12 exercise likely practiced a joint precision strike against South Korea designed to penetrate South Korea’s advanced IAMD network. The Russian military regularly combines ballistic and cruise missiles with long-range drones when striking Ukrainian infrastructure and population centers to complicate interception.[5] North Korea’s inclusion of long-range strike drones in the September 12 exercise is notable, and one variant of a drone used in the exercises bears some resemblance to a type of long-range drone used in Ukraine and the Middle East.[6] North Korea may be learning from Russian strike packages and is likely seeking to emulate them by developing more diverse strike capabilities.

The September 12 exercises also likely brought together units from the Korean People’s Army (KPA) Ground Forces, which are responsible for long-range artillery, and the KPA Strategic Force, which is responsible for long-range surface-to-surface missiles.[7] North Korea may be improving its ability to conduct joint strikes with units from both services, increasing the frontline support that KPA Strategic Force units may provide in a conventional conflict. ISW-CDOT has assessed that North Korea’s frontline artillery units may be shifting toward long-range strikes and away from tactical fire support, as reflected in the September 12 exercise’s inclusion of long-range artillery units in a long-range strike test.[8]

Improved joint strike capabilities likely increase the threat that North Korea’s conventional and nuclear forces pose to South Korea, although key limitations likely remain in the North Korean strike system. Russia’s long-range strike campaign has strained Ukrainian air defenses and created interceptor shortages, although this has not proved decisive to the outcome of the conflict.[9] North Korea also likely lacks the complex intelligence, surveillance, and reconnaissance architecture necessary to execute precision strikes effectively, although support from Russia or the PRC could remedy this shortcoming.[10] North Korea could still create significant effects without highly precise munitions if it can overwhelm South Korean IAMD with large and diverse strike packages.

North Korea is likely expanding its uranium enrichment facilities to increase its nuclear production and strengthen its nuclear forces’ survivability. The International Atomic Energy Agency (IAEA) assessed on September 9 that North Korea’s newly constructed uranium enrichment facility at the Yongbyon nuclear complex could accommodate up to 28 centrifuge cascades, a term that refers to a series of gas centrifuges that produce enriched uranium.[11] The IAEA assessed that the new two-story building at Yongbyon is likely North Korea’s second uranium enrichment facility.[12] The IAEA could not estimate the facility’s potential production of highly enriched uranium (HEU) or the number of nuclear weapons it could support due to the IAEA’s limited access to North Korean data.[13] The IAEA also reported that North Korea began operations in the Kangson enrichment facility in January 2026.[14] North Korea constructed the Kangson facility in 2024.[15] The IAEA concluded that the expansion of enrichment facilities indicates that North Korea’s overall uranium enrichment capacity is continuing to increase.

An unnamed Russian representative to the IAEA criticized the IAEA’s report for creating a “misleading” impression on September 10. The unnamed Russian representative stated the IAEA had not conducted inspections in North Korea since 2009, thus making its conclusions about North Korea’s nuclear infrastructure unreliable.[16] The unnamed Russian representative could have made this statement in defense of Russia’s ally. Russia-North Korea relations have increased significantly in recent years due to North Korea’s support for the Russian war effort in Ukraine.

Workers’ Party of Korea (WPK) General Secretary Kim Jong Un stated in June that North Korean nuclear production capabilities doubled in the past five years.[17] The Yongbyon facility expansion will improve uranium gas production efficiency due to the increased number of machines. ISW-CDOT previously assessed that the Yongbyon facility expansion addresses North Korea’s increased demand for enriched uranium.[18] Increased uranium production would help achieve Kim’s stated goal from the Ninth Party Congress in February to expand production of North Korea’s large nuclear warheads and tactical nuclear weapons.[19] North Korea likely aims to diversify delivery platforms and increase the quantity of nuclear warheads it possesses to make its nuclear forces more survivable against potential decapitation strikes.

South Korea’s ability to develop nuclear-powered attack submarines (SSN) may depend less on resolving nonproliferation concerns than on demonstrating a clear operational requirement for SSNs to the United States. The IAEA announced on September 8 that the South Korean government submitted its intention to begin consultations on arranging the required safeguard procedures to acquire SSNs.[20] South Korea has repeatedly stated that it will cooperate with IAEA safety protocols when developing SSNs. South Korea likely intends to quell concerns that Seoul is seeking nuclear latency by reaffirming its commitment to nonproliferation. South Korea has sought US support for submarine construction and fuel sourcing. US President Donald Trump approved South Korea’s plan to construct SSNs during an October 2025 summit with South Korean President Lee Jae-Myung, though such efforts would require approval from the US Congress. South Korea’s negotiations with the United States have not yet advanced, however, as South Korea has not explicitly stated the SSNs’ operational requirements, likely in anticipation of PRC protests. Strengthening the operational justification for South Korean SSNs to the US Navy — particularly the US Department of Energy’s Naval Nuclear Propulsion Program — may be more important for South Korea than addressing nonproliferation concerns.

US Chief of Naval Operations Daryl Caudle stated on September 9 that South Korea has little need for SSNs if they will not operate beyond waters near the Korean Peninsula. Caudle stated that South Korea should have a strong operational justification for developing SSNs rather than using them as a symbol of national prestige.[21] The South Korean Ministry of Foreign Affairs (MOFA) responded to the comment on September 11 by stating that the development of SSNs is intended to strengthen security on the Korean Peninsula, but did not state whether SSNs would support operations beyond South Korean waters.[22] Lee previously stated in October 2025 that South Korea’s existing diesel-powered submarines lack the endurance needed to track North Korean or PRC submarines.[23] Some media outlets, however, reported that Lee said “submarines close to the PRC” instead of “PRC submarines.”[24] The Lee administration has not yet announced how, or whether, SSNs would support US operations in the Indo-Pacific. South Korea would likely need to further clarify its intentions for its SSN program to advance negotiations with the United States, obtain access to enriched uranium required for operating SSNs, and secure congressional approval of a potential joint development agreement.