South Korea’s voters have resoundingly rejected the first two years of Yoon Suk-yeol’s presidency. The National Assembly elections on 10 April — widely expected to be close — turned into a landslide win for the opposition Democratic Party (DP), which will soon control 187 seats to Yoon’s ruling People Power Party’s (PPP’s) 108. While Yoon’s domestic standing has been damaged, it is not clear that foreign policy will change.

The Democratic Party’s landslide win falls short of the 200 seats necessary for the opposition bloc to override presidential vetoes. But it will make maintaining party cohesion Yoon’s most important challenge for the next three years.

That challenge has already begun. The PPP has already started to disintegrate around the president. Han Dong-hoon, Yoon’s protege and hand-picked leader of the party ahead of the elections, immediately resigned following the ballot box drubbing. Once touted as a 2027 presidential hopeful, those hopes may now be dashed.

As a Gallup Korea poll finds Yoon’s approval rate at 23 per cent, the lowest of his term to date, Yoon himself will likely face calls to resign from his own party. That is not unprecedented. Among previous presidents, only Moon Jae-in made it to the end of his term without changing his party affiliation. But Yoon’s predicament will be different. As a political outsider, Yoon had few allies within the PPP when he became its candidate ahead of the 2022 election. Not a natural bridge builder, Yoon has done little to establish new alliances during his time in office.

While his unbending approach to politics has made him mostly immune to his chronically low approval ratings, he has likely made more enemies than friends within his own party. So long as the National Assembly election loomed, budding internal vendettas could be papered over. But with the election now done and the president having led the party to the worst electoral defeat in its history, score settling from within his own party could commence.

The opposition is already ramping up calls for investigations into Yoon’s family and administration. One such bill, calling for an investigation into First Lady Kim Keon-hee, was passed by the National Assembly in December 2023 and was vetoed by the president in January 2024. At the time, the opposition lacked the votes necessary to override the veto.

With 187 votes, it still lacks that ability. But multiple surveys have found broad public support even among conservatives for a special counsel-led investigation into the first lady. Given Yoon’s diminished status, his standing within his party, public opinion and Kim’s lightning-rod status, the opposition may be able to entice the necessary conservative votes to override a presidential veto of the investigation.

If that happens, Yoon’s presidency could begin to spiral. Where such a spiral would end is anyone’s guess. And as all of this highly personalised political drama unfolds, the business of state will continue to demand the president’s attention.

The election results are unlikely to reshape Yoon’s foreign policy. South Korean presidents are given wide latitude in setting the direction of the country’s foreign relations, and Yoon has been unusually aggressive in pursuing better relations with Japan in particular. That has drawn pointed criticism from the leadership of the opposition. But the election is unlikely to alter Yoon’s engagement with Japan over the next three years.

Yoon’s first two years of engagement with Japan took place under almost identical conditions with opposition parties controlling 181 seats. His engagement with Japan was never popular with the public outside of his base and drew the ire of the opposition, but he never faced widespread protests because of it. And the low approval ratings that have been a constant throughout the first two years of his presidency were not tied to foreign policy but rather to a litany of missteps on domestic issues. Yoon has shown a willingness to ignore public opinion and soak up criticism from the opposition.

To that end, the Yoon administration will continue to strengthen ties with Japan, the United States and Europe. As domestic political turmoil increases, the president will be encouraged to intensify his efforts abroad now that it is clear there is no chance to advance a domestic reform agenda. Visits to Germany and Denmark scheduled for February 2024 were cancelled to keep the president at home ahead of the election. Those trips will be rapidly rescheduled and perhaps even expanded as the president resumes his role as the country’s number one cheerleader.

South Korea will remain at a legislative standstill. That will be to the detriment of the country as a whole but will not be a major impediment for Yoon. His reform agenda has long been ill-defined and the party has lacked a clear vision for the country. The administration’s best-known reform proposal was to abolish the gender equality ministry in a country that ranks dead last in The Economist’s Glass Ceiling Index since 2016.

On items of actual policy, cobbling together a veto override will be much more difficult for the DP. This will further delay much-needed reforms like those to the country’s pension system, which is projected to be depleted by 2055. But Yoon and the opposition are unlikely to agree on the required reforms, and the opposition will be wary of handing Yoon a perceived win.

Throughout his presidency, Yoon has made little effort to bring a highly polarised nation together. Instead, he’s pandered to his base and largely ignored public opinion on a range of issues.

Now, his inability to reach across the aisle will return to haunt him. These will be three very long years in the Yongsan Presidential Office.

Karl Friedhoff is the Marshall M Bouton Fellow for Asia Studies at the Chicago Council on Global Affairs.