On December 3rd, President Yoon Suk Yeol of South Korea attempted to impose martial law, which lasted only six hours before the opposition-dominated National Assembly voted it down. What factors led to Yoon’s declaration? Was Yoon’s attempt or the legislature's swift response surprising?

Yoon's attempt at martial law and the swift legislative response was unprecedented. I was in the country a week before Yoon declared martial law, and I had no idea this was coming. Originally, I thought it was fake news because South Korea is a vibrant democracy, so the last thing you would expect is martial law, especially given that President Yoon made liberal democracy and freedom centerpieces of his administration. In his inauguration speech, he used the word freedom over thirty times. For him to impose martial law then was shocking.

The factors that led to this juncture were political gridlock and polarization. Yoon is from the conservative ruling party, the People Power Party. He has accused the opposition Democratic Party of Korea of conducting “anti-state activities” to establish a legislative dictatorship, trying to impeach at least 22 of his government officials, and investigating his wife for various corruption scandals. For him, the last straw before declaring martial law was when the National Assembly blocked the budget he tried to pass since he did not have a majority. Yoon felt that there was no longer a functioning government. At first, I thought he might have simply “lost his cool,” and then declared martial law. Now, there are questions if the call was premeditated, as it seems like some of his close government and military associates may have discussed launching something like a coup. That said, it is unclear if they intended to go through with it (the coup) and impose martial law for an extended time. Yoon’s most immediate reason for imposing martial law was this idea of political gridlock and opposition resistance.

South Korea’s top court, the Constitutional Court, has 180 days to consider reinstating Yoon’s presidential powers. Given the unprecedented nature of these charges, does the Court have much leeway? Is there much danger of another insurrection by Yoon’s supporters? 

Six hours after Yoon declared martial law, the National Assembly voted it down. According to the Constitution, the president is supposed to inform the cabinet about martial law, which President Yoon did not properly do. National Assembly members rushed to parliament to make a vote. However, Yoon had the military block lawmakers from entering the chambers, as if he was trying to stop them. However, lawmakers still entered and the opposition party with majority seats voted martial law down. Given this (outcome), we can take some solace that the democratic institutions are functioning as they should in South Korea right now.

The Constitutional Court now has 180 days to consider whether he indeed committed an act that justifies impeachment, or if he should be reinstated. Likely this may only take 40-80 days because there are technical reasons why they want to make this decision sooner rather than later.

We’ve already seen insurrection by Yoon’s supporters when he was arrested. It took a couple of weeks to get him out of his house, and there was a standoff between riot police, the military, and the Presidential Security Service. As he was being taken to the district court to be indicted, some of his supporters came out and threw furniture and rocks through the glass windows of the courthouse. Those individuals are now being prosecuted. There is some fear that if the Court decides to uphold impeachment, his supporters may come out again and commit acts of violence. In addition, I'm concerned that if he's not impeached, there will be large protests. Protests in South Korea tend to be peaceful and relatively organized, as we saw right after (Yoon’s) martial law declaration. However, because this would be seen as unprecedented, there is an assumption right now that President Yoon made an impeachable offense, so we might see violence even from those who support the opposition. While the democratic process is moving through in a way that's peaceful and fairly organized, it doesn't mean that there will not be violence at some point after the court makes a decision one way or the other.

What are the main implications of the full series of events for Korean democracy? Is this a sign of strength or weakness of Korean democracy?  

On one hand, we are seeing the resilience of South Korean democracy, even though the president made the unprecedented call for martial law. We have seen pushback that one man cannot just enforce martial law or his laws by decree. Civil society sees that the National Assembly can overturn martial law. Even in the courts, they're giving President Yoon due process, ensuring that all the steps and procedures are followed, reviewing the actual actions that he takes, and listening to what President Yoon and his associates have to say. They are not laying a blanket statement that he is “guilty” just because he’s declared martial law; there is a process. This is a testament to signs of strong democratic institutions.

On the flip side, it is abnormal to have a second impeachment within eight years. Almost back-to-back impeachment cases are not normal for democracy. If you dig a bit further, we must ask ourselves, how did South Korea get into this situation? In response, my research talks about nationalist polarization. There are norms of democracy where you learn to tolerate and respect other opinions and exercise forbearance for the opposition party. These (norms) are lacking these days, and polarization is more deeply ingrained. I say nationalist polarization because it's like the winning teams are rivals. Right now, it is “either my way or no other way”, but it should be about the future vision of what South Korea should look like. Neither side can agree on this, so they are stonewalling each other's initiatives in cycles of political retribution. When one party comes to power, they start investigating the other side. Often, these investigations are politically rather than legally motivated. This happens for both parties, although it is a bit more egregious on the conservative side. These challenges to norms and cycles of retribution are weakening Korean democracy. Sadly, even if President Yoon is impeached and there is another election, these problems are not necessarily going to go away.

We are seeing this trend of lost democratic norms and forbearance all over the world. Do you have any insights as to why that is and why we keep seeing these problems with different leaders?

Many political scientists are trying to explain increased polarization and the populist movements developing in countries otherwise seen as strong democracies. There are several factors.

Part of it is social media and how the media deploys disinformation. In the case of those who incited violence after Yoon’s martial law was voted down, many of those individuals listened to far-right YouTube channels and were socialized into thinking that the opposition was communist or had been co-opted by North Korea. While this sounds ridiculous, YouTube is big in South Korea, and many have been socialized into thinking that the country is under attack.

In addition, people find that the stakes are becoming higher and higher. Unemployment has been a long-time issue, the birth rate is declining, and there is social angst. This makes people lash out and want to find a scapegoat. In South Korea's case, this could be contributing to that polarization.

Rhetoric also plays a role, especially in the United States and Europe. Certain words have been a lightning rod that fearmongers use and exacerbate polarization. For example, many think immigrants and migrants are coming into the country, taking away jobs, and committing crimes.

North Korea has long posed a threat to South Korea, which may have been further exacerbated by Pyongyang’s expanded areas of collaboration with Russia, including the signing of the 2024 Treaty on Comprehensive Strategic Partnership. How concerning is the strengthening relationship between North Korea and Russia for South Korean security?

Independent of what happened with martial law, growing ties between North Korea and Russia are a deep concern, in part because North Korea is set on expanding its nuclear and weapons capabilities. They haven't been able to achieve the technology that allows this yet, which they call (ICBM) vehicle re-entry (capability). If you attach a nuclear warhead to an intercontinental ballistic missile (and launch it), it has to come back into the atmosphere without burning up. North Korea has not figured out this technology, but the fear is Russia could share (that technology). North Korea is interested in launching satellites into space, and that's certainly something that the Russians can help them with as well. South Korea is vulnerable as North Korea is marching forward with its weapons capabilities and we should be concerned.

The relationship between Russia and North Korea goes beyond just the Ukraine war. A lot of attention has been given to the supply of munitions and artillery shells from North Korea to Russia, but 12,000 North Korean soldiers were fighting on the Ukraine front. This relationship for both Kim and Putin has benefits that can go beyond the length of the Ukraine war. This gives Kim Jong Un longer-term support, and he is not as isolated as we once thought he was.

In terms of the martial law declaration, there is a question of whether this threat boiled to a point where it justified a state of security and clamp down on freedom of speech and communications. This is not the case. The threat kind of sits there (i.e. a constant threat) and Koreans have learned to deal with it for decades. While it has been rising, the threat is incremental and not something that (developed) overnight. While some say North Korea is more likely to attack or conduct some kind of provocation toward South Korea because of South Korea's current political disarray, I disagree. President Yoon Suk Yeol declared martial law because he claimed that North Koreans were ready to attack and had infiltrated society. North Koreans are cautious, and they are not going to take advantage of the political disarray in South Korea right now.

The reelection of Donald Trump is straining relations with traditional American allies and partners. How may this affect South Korea’s relations with the United States? As an important economic, technological, and military partner, how stable or vulnerable is the U.S.’s relationship with South Korea? 

President Trump likes alliances to the extent that he can get something (i.e., economic, military support, etc.) out of it. He does not want to get rid of alliances, but the way he treats allies is very different from previous presidents which is causing a lot of angst in Seoul. In South Korea, there are fears of “South Korea passing,” where President Trump does not care about South Korea, especially given the political situation. Many are afraid that he will make demands, as he has talked about the trade imbalance with South Korea. South Korea had a $55 billion trade surplus in 2024, which is a deficit for the U.S. and does not look good for Trump. Trump called South Korea a “money machine” during his campaign and said he would make them pay $10 billion for the lion's share of the burden (they currently pay about $1 billion).  I expect that there will be tension and strain as they negotiate trade deals and share the burden. However, whoever becomes the next leader in (South) Korea will want to work with the United States. In addition, if President Trump wants to be more confrontational with China and put forward a military primacy strategy for the Indo-Pacific, he will not be able to do it without the US troops in South Korea or support from alliances. Koreans may be a bit reluctant, but overall, they will find a way to make the relationship work despite the demands Trump makes on allies.