U.S.-South Korea Pact Expands to Counter China as North Korea's Threat Lingers

The U.S. military's strategic flexibility in South Korea is under renewed scrutiny as Washington and Seoul navigate evolving regional security dynamics. During a recent visit to the Demilitarized Zone (DMZ), U.S. Defense Secretary Pete Hegseth emphasized that while deterring North Korea remains the core of the alliance, the U.S. is considering expanded operational roles for its troops in the region — including potential deployment in conflicts beyond the Korean Peninsula such as those involving China — though Hegseth stressed North Korea remains the primary focus, a VOI report noted. The remarks align with broader U.S. efforts to adapt its forces to a shifting geopolitical landscape, including regional contingencies like Taiwan's defense, Al Jazeera reported.

South Korea, meanwhile, is bolstering its military capabilities. President Lee Jae Myung announced a historic 8.2% increase in defense spending for 2026, raising the budget to 66.3 trillion won ($46 billion) — the largest hike in six years. The government also plans to triple investments in artificial intelligence to $7 billion, aiming to position itself among the world's top three AI powers, according to Al Jazeera. These moves reflect Seoul's long-term strategy to eventually assume wartime command of joint U.S.-South Korean forces, a goal it has pursued for over two decades, as reported by VOI.

A key development in U.S.-South Korea cooperation is the potential construction of nuclear-powered submarines by South Korea, with U.S. support. Washington's approval, announced by President Donald Trump, allows Seoul to pursue the project, with the first submarine expected by the mid-2030s if fueled by U.S. technology, the Economic Times reported. Defense officials noted that securing fuel through consultations with the U.S. is critical, and South Korea's advanced conventional submarine industry positions it to manage the project. However, the U.S. has not clarified whether the submarines would be built in South Korea or at U.S. shipyards, as Trump suggested.

North Korea's recent military activities underscore the urgency of these plans. During Hegseth's visit, Pyongyang fired artillery rockets near the DMZ, with South Korea's Joint Chiefs of Staff attributing the launches to heightened regional tensions, TRT reported. North Korea has also dismissed denuclearization as a "pipedream" and deepened ties with Russia, sending troops to support Moscow's war in Ukraine.

The U.S. and South Korea also agreed to enhance logistical cooperation, with Seoul committing to maintain and repair U.S. naval vessels to ensure readiness in regional crises, according to Al Jazeera. This partnership aligns with broader U.S. goals of maintaining a flexible military footprint in Asia, as outlined in recent policy discussions reported by VOI.