The United States Allowed South Korea to Build a Nuclear Submarine in Philadelphia

The United States has officially approved South Korea’s plan to build a nuclear submarine at the Hanwha Philly Shipyard in Philadelphia.

The decision was made after US President Donald Trump met with South Korean President Lee Jae-myung on October 29 in Gyeongju, Army Recognition reports.

The submarine will have a nuclear power plant, allowing it to remain underwater for several months without surfacing, reducing the risk of detection.

Hanwha Philly Shipyard, located on the former naval shipyard site in Philadelphia, previously specialized in commercial vessels such as tankers and container ships.

The company acquired the facility in December 2024 for $100 million and announced $5 billion in investments to expand its capacity. The construction of a nuclear-powered boat will require licensing, the creation of protected zones, and the training of qualified personnel.

Trump called the project a step toward the revival of American shipbuilding, while Lee called it a means to modernize defense cooperation. Seoul emphasized that it does not seek nuclear weapons, but only access to fuel for power plants. The parties agreed to further consultations on technical implementation and regulatory support.

Today, the South Korean Navy has 21 diesel-electric submarines of three types: KSS-I, KSS-II, and KSS-III. The newest KSS-III, built in-house, includes nine units in two series. The first two boats have already been commissioned, and the third is at the outfitting stage. By 2031, South Korea plans to complete the KSS-III program, which will allow for the gradual decommissioning of older models and strengthening of maritime defense.