North and South Korea race for nuclear-powered submarines as U.S. eyes China
North Korea released images of what it calls an 8,700‑ton nuclear-powered strategic guided‑missile submarine, the first public disclosure of tonnage and a seemingly completed hull since it announced a nuclear‑submarine program in 2021. In response, South Korea — after U.S. approval — has created a pan‑government task force and is negotiating U.S. supply of military nuclear fuel to build its own nuclear‑powered boats, moves U.S. and South Korean officials frame as part of combined deterrence goals against China amid concerns diesel submarines lack comparable endurance and speed.
📌 Key Facts
- North Korea released details claiming an '8,700-ton nuclear-powered strategic guided missile submarine,' the first time Pyongyang has disclosed a tonnage figure and shown what appears to be a completed hull since declaring a nuclear-submarine pursuit in 2021.
- After receiving U.S. President Trump's approval in October, South Korea created a pan-government task force to develop nuclear-powered submarines and is working on a pact for the United States to supply military-use nuclear fuel.
- South Korean Defense Minister Ahn Gyu-back said in October that the country's diesel-powered submarines 'can't compete' with North Korea's nuclear submarines in underwater endurance and speed.
- U.S. Chief of Naval Operations Admiral Daryl Caudle said in November it is a 'natural expectation' that future South Korean nuclear submarines be used to meet U.S.–ROK combined goals against the U.S.'s pacing threat, China; South Korean President Lee Jae Myung made a rare explicit reference to China at an October summit with President Trump, which was interpreted as aligning with those U.S. expectations.
- Taken together, these disclosures and policy moves signal a growing nuclear-powered submarine arms race on the Korean Peninsula and increasing U.S.–South Korea alignment to employ such capabilities in the broader strategic competition with China.
📊 Relevant Data
South Korea's development of nuclear-powered submarines is estimated to cost around $7 billion for the first vessel, with potential total investments reaching $150 billion as part of broader shipbuilding cooperation with the U.S.
The logic behind South Korea's nuclear submarine deal — Lowy Institute
North Korea faces significant technological challenges in building a nuclear-powered submarine, particularly in developing a small nuclear reactor for propulsion, which remains a major gap in their capabilities.
North Korea's Nuclear-Powered Missile Submarine: A Mystery Wrapped Around a Riddle and an Enigma — 38 North
The introduction of nuclear-powered submarines by North Korea could accelerate an arms race in Northeast Asia, increasing instability and prompting military responses from South Korea and Japan.
Strategic Implications of North Korea's Nuclear Submarine Development — RealClearDefense
China has warned that U.S.-South Korea cooperation on nuclear-powered submarines poses serious threats to nuclear non-proliferation and regional security in Northeast Asia.
Chinese expert warns proliferation risk as South Korea, US plan nuclear-powered submarine cooperation — Global Times
Non-proliferation concerns with South Korea's nuclear submarine plans include the risk of setting a precedent for other non-nuclear states to pursue similar technology, potentially undermining the Nuclear Non-Proliferation Treaty (NPT).
How nuclear submarines could pave the way for nuclear weapons in South Korea — Bulletin of the Atomic Scientists
📰 Sources (2)
- Provides North Korea’s claimed tonnage and description of the boat as an '8,700-ton nuclear-powered strategic guided missile submarine' and states this is the first time Pyongyang has disclosed the tonnage and a seemingly completed hull since declaring its nuclear-sub pursuit in 2021.
- Reports that South Korea, after receiving President Trump’s approval in October, has created a pan-government task force to build its own nuclear-powered submarines and is working on a pact for the U.S. to supply military-use nuclear fuel.
- Quotes U.S. Chief of Naval Operations Admiral Daryl Caudle in November saying it is a 'natural expectation' that future South Korean nuclear subs be used to meet U.S.–ROK 'combined goals' against what the U.S. considers its 'pacing threat,' China.
- Notes that South Korean Defense Minister Ahn Gyu-back publicly argued in October that the country’s diesel-powered submarines 'can't compete' in underwater endurance and speed with the nuclear submarines North Korea is building.
- Indicates that South Korean President Lee Jae Myung made a rare, explicit reference to China in his October summit with President Trump, interpreted as aligning with U.S. expectations about using South Korean nuclear-powered subs in the broader regional contest with Beijing.