Following months of political turmoil, South Korea's upcoming presidential election could lead to a shift in the country's approach to the U.S.-China rivalry, with candidates' stances influencing South Korea's policies on defense, trade, and diplomatic relations with both powers. While Lee Jae-myung may seek closer ties with China, potentially boosting trade and cultural exchanges, his rival is expected to strengthen South Korea's alignment with the U.S., especially on security and technology-related matters.
Lee Jae-myung delivers his speech during a national convention of South Korea's Democratic Party to choose their candidate for upcoming presidential election, in Goyang, South Korea, April 27, 2025. (Photo: REUTERS/Kim Hong-Ji)
The past six months in South Korean politics have been tumultuous, to put it mildly. On December 3rd, 2024, then-President Yoon Suk Yeol declared martial law, castigating the opposition of seeking to “overthrow the free democracy” of South Korea. A dramatic protest forced Yoon to withdraw his decision.
The country has subsequently undergone three acting Presidents. With the formal removal of Yoon from office in April 2025 after a Supreme Court ruling, the election for his successor was called for June 3rd – six months since the fateful date.
Opposition leader Lee Jae-myung – a long-standing stalwart from the Democratic Party with no shortage of historical controversy – will be facing off against the erstwhile Employment and Labour Minister Kim Moon-soo, with former Acting President Han Duck-soo dropping out to support Kim in a coalition agreement reached mid-May. The race presently has seven candidates, with two serious contenders.
Given the checkered track records of both major parties, the upcoming election is likely to be a vote on the “least unpopular candidate”. That is, those opting for Lee would likely be driven more by repulsion at Yoon’s prototypical authoritarian tendencies, corruption, and fundamental ineptitude, than by any genuine support for the vision articulated by Lee. Similarly, those voting for Lee’s opponent are unlikely to be particular fans of Yoon’s leadership – but are merely more wary of the prospects of having a left-wing occupant of the Blue House.
From a regional geopolitical perspective, a most intriguing question thus emerges: would the victory of either of these candidates bring about a reset to the country’s response towards the burgeoning Sino-American rivalry – that is, its U.S.-China policy?
The structure fights back – where leadership-centric analysis falls short
Given the pre-eminence and outsized influence of the President on the state’s decision-making, it would be reasonable to conclude that the results of the June 3rd race can and will have a palpable impact on Seoul’s orientation towards Beijing vis-à-vis Washington. Yet we must be careful not to overstate the role and significance of individual politicians – especially given the prevalence of three structural considerations shaping Sino-U.S.-South Korean relations.
Firstly, South Korea has long been a definitive and sturdy security partner to the U.S. in the region. The 1953 U.S.-ROK Mutual Defence Treaty firmly bound South Korean security to Washington – not just in the context of the frozen Korean Peninsula conflict, but also vis-à-vis other prospective rivals jostling against the U.S. for regional strategic influence. Despite the patchy, ad hoc criticisms by President Donald Trump during his first term, the U.S.-backed Terminal High Altitude Area Defense (THAAD) remains an instrumental component of Seoul’s line of defense against potential aggression by Pyongyang.
Of course, Lee has, in the past, criticised THAAD; in the run-up to the 2022 election, he vocally opposed the installation for its being “out of line with our national interest”. Yet he also notably conceded that THAAD was a “given reality”. Indeed, with the increasing, attention-craving displays of aggression by North Korea – no less spurred by the precipitously consolidated partnership between Pyongyang and Moscow – any minimally savvy South Korean President would likely refrain from deviating from the overarching consensus held amongst the bipartisan elite in Seoul: ROK-U.S. military and security cooperation must and should be maintained.
Secondly, irrespective of partisanship, the newly inaugurated Blue House occupant must contend with a radically different White House than three years ago. Whilst erstwhile President Joe Biden sought extensively to pave over historical tensions between Japan and South Korea, convening a meeting with both South Korean and Japanese leaders at Camp David in an attempt to usher in a “new era of partnership”, his successor has exhibited far less patience and interest in maintaining multilateral institutions.
From its flagrant criticisms of NATO and erratic flip-flops over security guarantees for Ukraine, to the airing of vitriolic disgruntlement towards the European Union, the Trump administration has signalled explicitly to the international community that it is likely to be far more transactional, driven by short-term interests, and systemically suspicious of international security treaties and defence pacts – especially ones where the other members are failing to put in what Trump views to be “their shift”. The incoming President would thus be compelled to address the many “what-if” contingencies – what if Washington demanded that Seoul paid up in full for THAAD? What if Trump demanded significantly more purchasing of American goods to close the limited bilateral trade deficit, in exchange for military and security guarantees? What if Trump sought to recreate the failed Hanoi summit with another meeting with North Korean leader Kim Jong-un?
These questions behove prudence, as well as a willingness to engage in strategic hedging, from the newly elected leader, in maintaining a modicum of ambiguity towards the Sino-American relationship, and rekindling frayed trade, financial, and cultural-educational ties with China.
Thirdly and finally, there thus exist clear upsides in South Korea’s pursuing closer ties with its Southern neighbour – only if it approaches the relationship pragmatically, with clear eyes that pierce through the rhetoric. Alarm bells have gone off at the fact that the ROK-China trade dynamic was reversed in 2023, when South Korea recorded its first deficit with China in 31 years. This deficit is expected to grow, as China invests continually into advanced and high-value-added manufacturing – a domain in which South Korea had long held palpable a technological lead.
On this front, the crux hence lies with whether Beijing and Seoul can navigate their way towards a new modus vivendi: one in which China substantially opens up its domestic market access for South Korean producers, undertakes more fruitful and productive investments into its northern neighbour, as well as committing to assisting Seoul with tempering the geopolitical ambitions of the Kim regime. The jury is still out – it would be premature to write off the Sino-South Korean relationship; key breakthroughs could still be reached, especially given Beijing’s ongoing diplomatic charm offensive, which speaks to a genuine desire from the very top in mending rifts with neighbours and members of the Global North.
Why leadership can and still matters, somewhat.
One may wonder, “What gives?”
Does the near-term question – who wins the race – matter all that much for the country’s Sino-American relationship?
The answer lies to the affirmative, with the above comprising clear caveats. There remain three areas of divergence between Lee and his rival, of which we should take note.
Firstly, Seoul’s stance on North Korea would likely differ in subtle but important ways. Lee has vowed to rebuild “mutual trust” with the country’s northern neighbour, advocating the restoration of the 2018 inter-Korean military pact and halt cross-border negative “propaganda” activities if elected. How much of this comes down to a desire to stake out visible differences from his predecessor’s hard-lined stance during the campaign, remains to be seen. On the other hand, both of his opponents have called for shoring up relations with the U.S. and Japan to combat the threat from Pyongyang. A victory by Lee could thus give rise to more of a proactive effort to re-kindle relations with Pyongyang with support from both Washington and Beijing – a daunting ask that China would nevertheless view with some trepidation, given the complex entanglement of interests and plethora of unresolved disagreements in the peninsula.
Secondly, Lee would likely be in favour of more cultural, educational, people-to-people, and civil society-led exchanges between South Korea and China. He has long been panned by critics of being unduly deferential towards China, a charge that carries much (detrimental) weight in a population where – according to a 2022 survey – four out of five held negative or very negative sentiments towards China. In contrast, should his rival be elected, there would likely be more scrutiny of inter-cultural exchanges, framed through the lenses of defending the country from ostensible infiltration and interference by external powers. The next few years could prove to be pivotal in shaping the attitudes and trust of the next generations of South Koreans towards China.
Thirdly and finally, the extent to which Seoul would be receptive towards Beijing’s push for more trade integration and connectivity, would also vary across candidates. Whilst Lee’s nominally left-wing credentials should render him sceptical of further trade liberalisation, in practice, his proclivity towards shoring up the warmth and depth of economic and investment ties with Beijing, could well drive him towards negotiating further augmentation to the existing China-South Korea Free-Trade Agreement. On the other hand, as it stands, the prospects for a China-Japan-South Korea Agreement remain more symbolic hot air than a substantive policy proposal.
In contrast, should Lee’s opponent clinch a victory, he would likely tilt South Korea in Washington’s direction, on fronts ranging from compliance with sensitive technological restrictions to tariff negotiations, from cracking down on re-exports of Chinese-originating goods to the U.S., to other areas in which Washington construes Beijing as a systemic strategic rival.
As an informal rule of political science, within parameters defined by structural factors, individual leaders retain a modicum of agency to exercise discretion, which could turn out to be causally significant – pending the quality of their and their surrounding advisors’ judgment.
This adage applies particularly well to South Korea today.
