Seoul: A second administration under Donald Trump is anticipated to bring changes and unpredictability to the U.S.-South Korea alliance, potentially increasing pressure on Seoul to assume a larger share of the responsibilities as a U.S. ally, experts stated on Wednesday.According to Yonhap News Agency, a primary concern will be how Trump might handle North Korea's denuclearization, amidst rising skepticism about Washington's commitment to this objective, and his strategy towards Russia's war in Ukraine, where North Korean troops have reportedly been deployed to support Moscow. Trump, recognized for his transactional perspective on alliances, may attempt to renegotiate the defense cost-sharing agreement with South Korea, possibly increasing Seoul's financial contribution for stationing the 28,500 U.S. troops in the region.Choi Kang, president at the Asan Institute for Policy Studies, noted, "The first thing he'll likely do is 'anything but Biden,' and for him, the defense cost deal will be one of the easi est ways to demonstrate that to the outside world." Recently, Seoul and Washington agreed on a new five-year Special Measures Agreement (SMA) until 2030, under which South Korea will gradually increase its payment, reaching 1.52 trillion won ($1.19 billion) by 2026, with further adjustments based on consumer price index changes.During Trump's initial term, previous SMA negotiations were intense and only resulted in a one-year agreement, which was later resolved at the start of the Biden administration. Trump had insisted that Seoul pay up to $50 billion for the maintenance of American soldiers. Throughout his campaign this year, Trump labeled South Korea as a "very wealthy" nation and a "money machine," hinting that the U.S. might withdraw its troops from South Korea unless Seoul boosts its financial contributions to support them.Trump could potentially leverage the SMA to reduce the allies' joint military exercises or demand a greater share of the costs for the U.S. deployment of strategic assets to Sout h Korea, according to Park Won-gon, a professor at Ewha Womans University. "Trump could certainly readjust the role of USFK, if not withdraw them entirely, and consider repositioning the troops to locations outside the Korean Peninsula as a way to counterbalance China," Park stated. "We should be prepared to deal with these possibilities."Trump's "cost-benefit" approach to alliances may also extend to U.S. involvement in the increasing number of minilateral security partnerships of like-minded nations, such as the trilateral cooperation framework with South Korea and Japan, as well as the AUKUS partnership involving Australia, Britain, and the U.S. Professor Park mentioned, "Trump wouldn't backtrack on the Camp David (summit)," referring to last year's trilateral summit among President Yoon Suk Yeol, U.S. President Joe Biden, and then Japanese Prime Minister Fumio Kishida.The Indo-Pacific strategy was present even during Trump's term, and he may try to utilize these partnerships to explicitly make more de mands as they can alleviate some of the burdens the U.S. shoulders for its allies. Meanwhile, Trump's handling of Russia's war in Ukraine could have implications for North Korea's deployment of troops to Russia. Concerns about an escalation of the war are growing amidst reports that North Koreans sent to Russia are actively engaged in combat in front-line areas to fight alongside Moscow. Trump has claimed he can end the war "in one day."Choi remarked, "I'm not sure how seriously Trump views North Korea's troop deployment, and that is a variable to watch. We can only hope that he will consider options for an early ceasefire, if not an end to the war, sometime soon, considering its potential impact on the North Korean troops."Attention is also focused on how a second Trump administration would approach North Korea's denuclearization, given the past of a failed nuclear summit with North Korea's leader Kim Jong-un during his first term. Recently, the absence of the phrase "complete denuclearization of the Kor ean Peninsula" from the policy platforms of both the U.S. Republican and Democratic parties has sparked questions about a potential shift towards effectively recognizing North Korea as a nuclear-armed state, away from pursuing its denuclearization."Trump is a man of extremes, but I think he would rather maintain the status quo than have another summit with Kim Jong-un," Park said. "The absence of denuclearization in the policy platforms suggests that the U.S. is focusing on the deterrence strategy against North Korean threats. Moreover, Trump will likely need to prioritize the war in Ukraine and the situation in the Middle East."Chun Yung-woo, chairman of the Korean Peninsula Future Forum think tank, advised against overinterpreting the lack of the phrase. "We shouldn't view this as the U.S. giving up (on North Korea) just because it's been pushed to the back burner," Chun said. "What is crucial is to continue our denuclearization policy in a way that protects and advances our national interests."Choi f rom the Asan Institute suggested that Seoul push for an early summit between Yoon and Trump to reaffirm the alliance commitment. "We should take the 'top-down approach' favored by Trump," Choi said. "Having an early summit would allow us to reach broader agreements."
- October 12, 2026
