September 25, 2025

Information Cutoff: 5 PM ET, September 22

Karolina Hird, Grace Mappes, and Johanna Moore, with Nicholas Carl

North Korea and the People’s Republic of China (PRC) have broadcast in recent weeks the central role that drones play in their military modernization programs, demonstrating how US adversaries are learning from the war in Ukraine. North Korean leader Kim Jong Un visited the Unmanned Aerial Technology Complex at the Panghyon Airbase on September 18 and inspected combat and reconnaissance drones, calling their development a “top priority” for modern warfare. Kim watched performance tests of the Kumsong attack drone and the Saetbyol-4 strategic reconnaissance drone. The Kumsong has two variants — an X-wing model that is virtually identical in appearance and intended function to the Russian Lancet-3 loitering munition and a delta-wing aircraft-type that resembles the Israeli IAI Harop loitering munition. Kim ordered the North Korean military to strengthen its drone capabilities with artificial intelligence (AI) during the visit.

Russia reportedly provided North Korea with a reactor for a nuclear-powered submarine, likely bringing North Korea years closer to operating a nuclear-capable submarine. South Korean intelligence reported that Russia provided up to three nuclear submarine modules to North Korea sometime between January and June 2025. South Korean intelligence reported that Russia provided a nuclear reactor, turbine, and cooling system from a decommissioned Russian nuclear submarine. These are the three core components of a nuclear propulsion unit. Nuclear submarine propulsion units convert the heat that reactors generate into energy to power the submarine. This process does not require air or oxygen and therefore allows the submarine to remain submerged underwater until it needs to resupply food for its crew. South Korean intelligence reportedly shared this intelligence with the United States. South Korean officials have not publicly confirmed this information.

Russia’s provision of military technology to North Korea will augment North Korea’s power projection capabilities in the Western Pacific. North Korea previously lacked the necessary technology and production capacity for a nuclear-capable submarine and nuclear reactor, but Russia’s reported provision of a nuclear reactor specifically for a nuclear-capable submarine has removed much of North Korea’s barrier to constructing such a vessel. Ukrainian Main Military Intelligence Directorate (GUR) head Lieutenant General Kyrylo Budanov indicated in June 2025 that Russia was helping North Korea develop its submarine-based nuclear deterrent. North Korea published images reportedly displaying a nuclear-powered submarine under construction as of March 2025 — around the time of the reported Russian deliveries. The Telegraph reported on September 22 that Russia considered providing North Korea with nuclear reactors that could power either a submarine capable of launching cruise missiles or a vessel capable of launching ballistic missiles. South Korean outlet JoonAng reported that North Korea had asked Russia for nuclear reactors for its submarines since 2024 and that Russia finally agreed due to North Korea’s support of Russia’s war in Ukraine. Russia likely would not have been willing to provide North Korea with such technology if not for North Korea’s support of the war in Ukraine.

• North Korea and the People’s Republic of China (PRC) have broadcast in recent weeks the central role that drones play in their military modernization programs, demonstrating how US adversaries are learning from the war in Ukraine.

• Russian assistance has likely brought North Korea years closer to operating a nuclear-capable submarine and will likely affect the broader balance of power in the Western Pacific.

• Russian energy cooperation with Iran strengthens the Russo-Iranian relationship by supporting Iranian efforts to provide basic services to its population while providing Russia with a market to sell sanctioned energy products.

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