In just two intense weeks in December, politics in South Korea was dramatically transformed – ‘all changed, changed utterly’, as W.B. Yeats once described revolutionary upheaval. President Yoon Suk-yeol’s bizarre and anachronistic declaration of martial law late on 3 December suddenly plunged the country back into a high-stakes drama reminiscent of 1970s authoritarianism. It prompted an outpouring of public resistance as ordinary Koreans rallied to defend democracy by mobilising to protect their representatives when they voted to annul Yoon’s order at the Republic of Korea’s (ROK) National Assembly. Despite Yoon’s dispatch of special forces to block the parliamentary vote, popular resistance ensured that the Democratic Party (DP),  the majority voice in the Assembly and the principal opposition party challenging Yoon’s governing People Power Party (PPP), was able (with the support of 17 PPP members) to pass a special motion calling on Yoon to withdraw his extraconstitutional move to subvert South Korea’s Sixth Republic.

Within six hours of his late-night declaration, Yoon had bowed to political pressure from the Assembly and rescinded his original order. For the next two weeks, the country was dominated by political paralysis and uncertainty as Yoon defiantly justified his actions as a defence of democracy and an effort to resist ‘anti-state’, ‘pro-Pyongyang forces’ – an apparent critique of the progressive left-of-centre political opinions represented by the Democratic Party. In response, the opposition held two critical parliamentary votes to impeach the president – measures firmly backed by over 75 per cent of Korean citizens and which eventually ensured Yoon’s suspension from office on 14 December and the ushering in of a caretaker conservative government headed by Prime Minister Han Duck-soo, in his role as acting as interim president.

South Korea’s dramatic fortnight could not have come at a worse time. Overnight the country’s hard-won reputation as a vibrant liberal democracy and defender of rules-based order, at home and abroad, epitomised by Yoon’s own characterisation of South Korea as a ‘global pivotal state’, has been thrown into question and its strategic relevance as a key regional and international actor potentially jeopardised. North Korea, the authoritarian neighbour, exploited the turmoil in the South by labelling the Yoon administration as a ‘fascist dictatorship’. Ordinary South Koreans expressed shock and acute embarrassment at the unanticipated chaos at home. Meanwhile, South Korea’s key trilateral security partners, the United States and Japan, watched with dismay as the country appeared overwhelmed by political paralysis.

Notwithstanding the successful impeachment vote on 14 December, effective and long-term programmatic governance in South Korea will now be stymied by the need to await a ruling by the country’s Constitutional Court – a decision that could theoretically take as long as six months, but is likely to be delivered more rapidly, though still within months rather than weeks. If the impeachment vote is upheld by the court, as seems likely, President Yoon will be removed from office and the starting gun will be fired on a new presidential election that must happen within 60 days of the court’s impeachment ruling. Depending on how this timetable unfolds, the country could face a wait of up to eight months before it has a new president and an effective, functioning government.

In a further unexpected twist to the political drama, on 27 December the National Assembly voted to impeach acting president Han, citing his failure to endorse key measures to fill three key vacancies on the nine-member Constitutional Court. In principle, an impeachment vote by the National Assembly is effective if two-thirds of the court, six in total, choose to uphold the vote. Han’s reluctance to appoint the three additional justices raised opposition concerns that the vote might be lost if just one of the six serving justices failed to support impeachment. By a simple majority vote, the opposition party suspended Han from his role as acting president – an unprecedented action – leading to the appointment of Deputy Prime Minister Choi Sang-mok as a new acting president.

Domestically, the continuing standoff between the governing and opposition parties has created considerable economic uncertainty, with the South Korean currency, the won, plunging to its lowest level in 16 years. Political instability may also impose high costs on the ROK’s foreign policy. Anticipating a Trump presidency that is likely to be firmly transactional and focused on extracting substantial trade and defence concessions from the US’s junior ally, Koreans have good reason to worry that their country will be critically weakened diplomatically at a time of continuing bitter divisions at home and acute uncertainty abroad, while also facing the threat from a more confident and belligerent North Korea, which may be tempted to exploit the tensions in the south for its own political gain.

I was fortunate to have a ring-side seat for this unfolding drama, having arrived in Seoul on 2 December for an international conference. What follows is based, in part, on my conversations (some off the record) with government and opposition officials, as well as a number of academics and civil servants. After a week in Seoul, I moved on to Tokyo for another week of interviews and presentations, where, unsurprisingly, the situation in South Korea was the dominant topic of conversation. First draft analyses such as these will no doubt be revised by later historical research, but for now two key questions stand out: what prompted the current crisis and in particular the actions of President Yoon? And what are the likely consequences of the martial law declaration and the impeachment decision for the ROK’s politics, its foreign policy and the resilience of democratic governance in South Korea?

President Yoon’s character is the most compelling explanation for why the current crisis emerged and why, for now, it is proving so persistent and intractable. Yoon’s personal biography, from his university days to the present, indicate that South Korea’s leader lacks any direct political experience and is unused, if not actively resistant, to the notion of negotiation or compromise – key requirements for any successful leader. Unlike past ROK presidents, Yoon had no experience as a political leader or campaigner and has had, instead, a reputation for being fiercely single-minded, if not dogmatically committed to fulfilling his professional responsibilities. Prior to becoming president, he served as the country’s prosecutor general, having been appointed by the country’s then president, Moon Jae-in, in 2019 with an explicit brief to investigate cases of political corruption, including charges connected to senior officials of the former conservative administration of President Park Geun-hye.

Park had herself been impeached and removed from office in 2017 (at the time, the first ROK president to experience such an outcome) and was subsequently imprisoned for several offences, including influence-peddling by her close, unelected adviser Choi Soon-sil, illegal acquisition of bureaucratic funds and unlawful interference in the selection of conservative election candidates in legislative elections in 2016. Yoon’s appointment as prosecutor general was an opportunity for the progressive Moon administration to crack down on political corruption, particularly allegations surrounding former conservative officials. The selection of Yoon would have been seen by the Moon administration as an ideal opportunity to keep the conservatives on the defensive given Yoon’s reputation for prosecutorial doggedness and resolve.

Moon and Yoon eventually fell-out, as Yoon investigated officials associated with Moon’s own government, including the then justice minister, Cho Kuk. To compound this fracturing of the relationship between Moon and Yoon, after becoming president, Yoon appears to have authorised and supported prosecutorial investigations into alleged corruption by Moon and members of his family, as well as charges against Lee Jae-myung, the leader of the Democratic Party and Yoon’s own rival in the 2022 presidential election.

A key contextual element in this complicated cycle of investigation and counter-investigation is the professional ethos and reputation of prosecutors in South Korea. Senior lawyers are seen as excessively zealous and overly politicised and all too often are deployed by ROK presidents (whether on the left or the right) to attack their past and present political enemies. Senior officials I spoke to in Seoul, both conservative and progressive, stressed that Yoon’s uncompromising opposition to the left in South Korean politics and his unshakeable faith in his own political judgement have very much been shaped by his career and the wider ethos of the prosecutorial profession. Yoon reportedly clashed with past employers as a junior prosecutor and, as a consequence, found himself sidelined for fast-track promotions.

Amplifying Yoon’s rigid defence of his own judgement and actions is his self-righteous framing of politics in South Korea in uncompromisingly oppositional and above all moralistic terms. In Yoon’s world view there is no political ambiguity, no grey marginal space where negotiated settlements might be hammered out. This predisposition on Yoon’s part is also not new, nor is it an isolated response to the contemporary rivalry between the president’s office and the National Assembly. In a speech of 15 August 2023 marking the country’s liberation from Japanese colonialism in 1945 – a regular event in the political calendar, observed by all South Korean presidents – Yoon stressed the values of freedom and democracy (a theme that has been central to his foreign policy and a frequent part of his public statements), but then surprisingly pivoted to attack, albeit obliquely, his progressive political opponents for alleged disloyalty to the South Korean state.

The tone in Yoon’s address was striking and more reminiscent of the language of past authoritarian or proto-authoritarian South Korean leaders (such as Syngman Rhee) from the early days of the Cold War, when it was common for conservative figures to accuse their political rivals of being unduly sympathetic to North Korea. It is worth quoting extensively from the speech, since it provides an early foreshadowing (missed by many commentators at the time) of Yoon’s willingness to embrace the drastic step of announcing martial law. Here is the text in full:

The stark differences between the Republic of Korea that opted for and pursued freedom and democracy and North Korea that chose communist totalitarianism could not be any clearer. Nonetheless, still rampant are anti-state forces that blindly follow communist totalitarianism, distort public opinion, and disrupt society through manipulative propaganda. In a divided nation, the confrontation between liberal democracy and communist totalitarianism is a reality. And the activities of those anti-state groups are likely to persist. As the totalitarian forces disrupt and attack our societies, they take full advantage of the legal rights enshrined in free societies. That is the way they survive. The forces of communist totalitarianism have always disguised themselves as democracy activists, human rights advocates or progressive activists while engaging in despicable and unethical tactics and false propaganda. We must never succumb to the forces of communist totalitarianism. We must not be deceived by those who follow and serve them. At this critical juncture, having faith is of utmost importance. We must stand united in the spirit of solidarity, with an enduring conviction that freedom and democracy will prevail.

Yoon has made it clear that he views the Democratic Party as illegitimate – ‘criminals’ (in the words of one of my interviewees), and traitors to South Korea. He has bolstered his argument by accusing the left of being a ‘parliamentary dictatorship’, citing as evidence the DP’s willingness to use impeachment, on more than 20 occasions, to attack prosecutors, and recently, a national auditor, in order to thwart the will of the presidential executive branch, and in particular to cut sharply the government’s proposed national budget. Yoon also suggested, in a defiant speech on 12 December, shortly before the second successful impeachment vote two days later, that the Democratic Party was intentionally blocking security legislation intended to combat alleged Chinese threats to ROK security, while also serving the interests of North Korea, whether by undermining the economy, attacking the integrity of South Korean judges or by refusing to accept the results of the 2022 Presidential Election. In aggressive style, Yoon sought to frame the opposition as illegitimate as well as obstructive, citing alleged voting irregularities (engineered supposedly by North Korea) in the April National Assembly elections which had produced a clear victory for the DP over the PPP. In short, in Yoon’s terms: ‘The opposition-controlled National Assembly has become a monster that is destroying free and democratic constitutional order, instead of serving as its bedrock.’

To be sure, the opposition in South Korea is not blameless. The left has also embraced some of the uncompromising tone and Manichean logic of its conservative opponents, prompting the Stanford sociologist, Gi-wook Shin, to warn of the risk of South Korean ‘democratic decay’.  During his time as president, former President Moon talked sanctimoniously about the need to eradicate ‘deep-rooted evils’ in South Korea’s politics, an unsubtle attack on the country’s conservative politicians. Indeed, all too often, politics in South Korea has been overly plebiscitary in character, with too much reliance on street politics and public mobilisation of popular anger to counter political actors that are seen as out of touch, elitist, at times corrupt and, therefore, illegitimate in the eyes of voters. This reliance on the power of the crowd has exposed the limitations of South Korea’s institutional guard-rails and the increasing tendency to rely on drastic legislative measures, such as the use of impeachment, to push back against one’s political opponents.

There is no credible evidence, however, that the April National Assembly elections were unfairly conducted. Moreover, it is worth stressing that President Yoon’s political dificulties in pursuing his agenda reflected his declining popularity across the political spectrum, including from within his own party, where conservative rivals, such as the recent former leader of the PPP, Han Dong-hoon, had grown increasingly frustrated with the president. Yoon’s poor handling of a series of prominent issues, including political tensions with doctors and nurses, failure to combat basic commodity (especially food) inflation, disputes over working hours, and, most strikingly of all, serious reservations about the actions of the president’s wife, Kim Keon-hee, had all contributed to a precipitous decline in his popularity. Allegations that Kim, a private citizen, had engaged in insider trading and also had a decisive role in selecting parliamentary candidates for the conservatives, had prompted a huge public outcry and added to Yoon’s declining popularity. So much so that in September 2024 there were rumours that conservative politicians were deliberately leaking recordings of private phone calls by the president and his wife in an effort to embarrass Yoon and potentially force an opening for a rival conservative leadership bid.

Facing these negative headwinds, Yoon appears to have acted out of desperation in announcing martial law in direct opposition to the views of members of his own cabinet, who were cursorily consulted shortly before he made his late-night television broadcast. Implausibly, the president, in seeking to justify his actions in announcing and then withdrawing his martial law decree, claimed that he was simply trying to warn the opposition against engaging in destabilising politics. In reality, recent reporting from the South Korean media suggests that the president was intent on permanently incapacitating his political opponents – both on the left and the right – and may have been planning his martial law announcement months before his December declaration.

It was then revealed that Yoon had ordered the arrest of both the leaders of the DP and PPP (along with the Speaker of the National Assembly); that he may have instructed the military, no fewer than six times, in the early hours of 4 December to forcibly remove politicians from the National Assembly to prevent a vote on martial law; and that plans were afoot to incarcerate hundreds of politicians in facilities outside Seoul while also engineering manufactured ‘incidents’ to suggest that North Korean agents were seeking to come to the assistance of Democratic Party ‘allies’. All of these add up to an image of a president completely detached from political reality and intent on eradicating his political opponents. Much of this detachment appears to have derived from Yoon’s appetite for South Korean right-wing YouTube channels that promote a wide range of conspiracy theories highlighting the treasonous predispositions of left-wing politicians.

In announcing martial law, Yoon seems to have been taking a leaf out of the political playbook of Carl Schmitt, the pro-Nazi, authoritarian German philosopher of the early and mid-20th century. Schmitt argued that political leaders, confronted by dysfunctional liberal-democratic regimes such as Weimar Germany, were justified in temporarily seizing dictatorial power to defend a vulnerable republic against its domestic political opponents, handing back power only once the domestic crisis had been overcome. It is unclear if Yoon has read Schmitt, but it is striking that the political philosopher is back in vogue in East Asia (especially among Chinese conservative scholars). Moreover, in the early 1970s, Korean legal academics deployed Schmitt as intellectual ballast to defend Park Chung-hee, the former military coup leader and president of South Korea, when he was drafting the country’s new Yushin constitution, which was designed to drastically restrict the country’s political freedoms.

Fortunately for the integrity of South Korea’s vulnerable democratic institutions, Yoon appears to have been a poor coup planner, making at best half-baked efforts to prepare for the imposition of martial law. As Wi Sung-lac, a prominent DP legislator, foreign policy adviser to Lee Jae-myung (the DP leader) and former senior foreign affairs official told me: ‘The last time we faced a coup, in 1979, they cut all the telephone lines to our offices.’ This time, however, public communications were uninterrupted, as were free media publications, and Lee Jae-myung shrewdly broadcast his middle of the night emergency arrival at the National Assembly via social media, helping in the process to keep public attention firmly fixed on the popular resistance against Yoon’s unconstitutional intervention.

In addition to the public and the opposition parties rallying to defend democracy, South Korea’s military, particularly its ordinary rank and file members, appear not to have shared the president’s authoritarian instincts. The local commander sent to manage the special forces dispatched to the National Assembly reportedly ordered that no live ammunition be provided to the troops and instructed his forces to refrain from using violence against National Assembly members. While the country’s Defence Minister Kim Yong-hyun, and the head of the Defence Counterintelligence Command were both enthusiastically supportive of the martial law order (so much so that Kim dramatically tried to commit suicide after being first implicated in Yoon’s attack on the National Assembly), the bulk of the country’s military, both officers and conscripts, were far more cautious – a reassuring sign that the country’s political culture has become far more unambiguously democratic compared to the authoritarian era of the 1970s and 1980s.

Now that Yoon has been impeached, political life will be in stasis as the country awaits the decision of the Constitutional Court. Yoon remains defiant, even to the point of repeatedly rejecting (or claiming not to have received) summons both from the court and from prosecutors seeking to investigate the circumstances surrounding the declaration of martial law. Yoon plans to mount a vigorous defence of his actions, including deploying lawyers to the Constitutional Court to argue against the impeachment motion. However, his room for manoeuvre looks to have narrowed considerably, especially following the decision on 31 December by the Seoul Western District court to approve a warrant for his arrest to allow prosecutors from the country’s Corruption Investigation Office (CIO) to question him regarding his alleged abuse of presidential authority in announcing martial law. At the start of the New Year, the CIO is now in a stand-off with the President and his public supporters, assisted by the President’s Security Service. They refuse to grant access to the President’s personal residence to allow the arrest warrant to be implemented. Street politics and the power of the crowd are again being mobilised to block the effective working of the country’s political institutions.

For its part, the opposition initially sought to promote a two-pronged approach, doubling-down on its criticism of Yoon while adopting a conciliatory tone in its overtures to the governing party, citing the importance of bipartisanship, national unity, making clear, albeit conditionally, that it was looking to work constructively with acting president Han. With Han now replaced as acting president by Deputy PM Choi following an additional impeachment vote, passed by a simple majority vote rather than the two-third vote that is legally required to suspend an elected president, the hope for a bipartisan resolution to the crisis seemed to have evaporated. The governing PPP accused the DP of overreaching by relying on the impeachment weapon and political acrimony intensified between left and right in an already highly polarised political environment. In an effort to moderate some of this tension, acting president Choi has now approved the appointment of a further two additional justices to the court and it looks increasingly likely that it will soon have its full complement of nine justices.

If the Court upholds the impeachment vote, public attention will be focused on the presidential election. For now, Lee Jae-myung looks favourite to be the DP’s nominee and if nominated for the presidency is well placed to win the election comfortably with more than 50 per cent of South Korean public opinion expressing support for him. With over three quarters of Koreans backing the impeachment vote, the governing PPP looks thoroughly discredited and there is a risk that the party will fragment and reconstitute itself under a new name – a familiar pattern in a political system where parties have weak identities and are typically highly personalised around individual leaders who tend to govern in a top-down, non-consensual fashion. Much of the animating drive for the PPP in seeking to block the impeachment was less about its support for Yoon and more about its intense antipathy towards Lee, who it sees, with some justification, as a polarising and divisive figure.

Additionally, while Lee’s political prospects are now much improved, given Yoon’s impeachment, they are not entirely problem-free. He faces a number of controversial court cases, involving allegations of influence peddling, financial corruption, witness tampering and lying during the last presidential election campaign. To his defenders, Lee is a victim of political persecution by Yoon, who they claim used his influence over prosecutors to attempt unfairly to discredit his political opponent. Whatever the merits of this argument, the risk for Lee is that the courts may uphold any criminal convictions against him and, in the process, bar him for running for election as president. For now, the political momentum remains with Lee, but he remains a divisive figure who routinely prompts intense antipathy from conservative partisans, particularly among older voters in their 70s and above.

Lee has made bitter attacks on Yoon, particularly over the president’s foreign-policy focus on strengthening diplomatic and security ties with the United States and especially with Japan – a country which, at least when it comes to Japanese government actions, often produces strong emotional reactions from a wide swathe of South Korean public opinion acutely conscious of the still contentious legacy of Japan’s colonial domination of the peninsula from 1910 to 1945. Lee has frequently labelled Yoon as a ‘pro-Japanese traitor’ for his close alignment with Tokyo as part of the August 2023 Camp David agreement intended to enhance trilateral cooperation between the US, Japan and the ROK. Yoon also developed a close working relationship with then Japanese Prime Minister Kishida Fumio, in part by giving less attention to historical grievances in favour of a more forward-looking diplomacy.

In Tokyo, I found a sense of profound resignation among politicians, bureaucrats and academics that the martial law crisis has completely derailed the recent rapprochement between Seoul and Tokyo, and that there would be scant possibility of any continuation of pragmatic bilateral cooperation if the country elects Lee as its next president. In the weeks leading up to Yoon’s surprise martial law announcement, bilateral ties had already been partially destabilised by a lingering controversy over a jointly planned ceremony to commemorate Korean colonial-era labourers who had been forcibly conscripted by wartime Japan to work in Japan’s Sado Island gold and silver mines – a historical site that has recently been granted UNESCO special world heritage status. The Sado issue is a complicated one but at its heart differences exist between Japan and South Korea over how best to document, memorialise and interpret the experiences of Korean forced labour at the mines. Koreans want the historical narrative surrounding the mines to highlight the brutality meted out to the Koreans by the Japanese authorities. Conservative Japanese opinion is sceptical that Korean labourers were coerced and are more inclined to view the history surrounding the mines in a longer historical context that stretches back some three hundred years before the colonial era.

Japanese politics is also grappling with a crisis, albeit nothing on the scale of what is happening in South Korea. In October, the governing Liberal Democratic Party (LDP) under Prime Minister Ishiba Shigeru, (suffering the aftershocks from a series of damaging funding scandals under Kishida, Ishiba’s predecessor), was punished by the electorate in the lower house election and now governs as a minority administration, critically dependent on support from minor opposition parties. Ishiba’s weakness with the public is compounded by a lack of support from within his own party and the expectation is that his political future is likely to be short, perhaps lasting for just a few months until July’s upper house elections, in which the LDP is expected to perform badly, potentially paving the way for a leadership challenge that will unseat Ishiba. Domestic weakness in Japan and South Korea leaves both countries diplomatically weakened and potentially ill-equipped to negotiate with the incoming Trump administration.

In this context, the fear in Japan is that a Lee presidency will forestall any hope of continuing co-operation between Tokyo and Seoul and will wipe away much of the bilateral progress that has been achieved in the last four years. Back in Seoul, however, sentiment, especially among Democratic Party politicians, is less pessimistic. ‘Lee may have campaigned as a populist, but he will govern as a pragmatist in foreign policy,’ was one view presented forcefully to me. The reasons for this are easy to discern. While in the past, progressive presidents such as Kim Dae-jung, Roh Moo-hyun and, most recently, Moon Jae-in have tended to focus on diplomatic engagement with North Korea, and have been less inclined to commit time and energy to working closely with Japan, the current international context is less amenable to such a strategy. If Lee becomes president he will face a North Korea that is emboldened by its new comprehensive strategic partnership with Russia and potentially inclined to embrace potential diplomatic overtures from an incoming Trump administration, particularly if this provides the North with an opportunity to isolate Seoul from Washington – a longstanding goal of North Korean foreign policy. Moreover, a second feature of previous progressive ROK presidents’ foreign policy – rapprochement with China – is also less easily realisable than it once was given growing anti-Chinese sentiment amongst the South Korean general public.

In this situation, a new South Korean administration’s best option may be to promote a more autonomous diplomacy superficially and performatively, while in practical terms looking to maintain close co-operative ties with Tokyo and Washington. Nonetheless, assuming Lee is willing and able to pursue such a subtle foreign policy, the challenge will be convincing Japanese and US officials to invest time and energy working with and trusting South Korea. The martial law fiasco, while highlighting South Korea’s public commitment to democracy and the relative resilience of its institutional guardrails, has also underscored the volatile and seemingly unpredictable nature of its politics and the risk that emotionally driven populist politics will derail the best laid diplomatic and strategic plans.

The research for this article was funded in part by a grant from the Korea Foundation.