South Korea’s Presidential Impeachment Upheld: Domestic Uncertainty amid Global Chaos
David Yang | 18 April 2025
Summary
South Korean President Yoon Suk Yeol’s impeachment has been upheld by the Constitutional Court, officially removing him from office. The by-election is scheduled for 3 June 2025.
The election will only escalate political tensions after months of polarisation, with the Democratic Party (DP) only slightly favoured to win over the People Power Party (PPP). Increased policy uncertainty and lack of leadership amid United States (US) President Donald Trump’s tariffs are detrimental to the economy.
The military alliance with the US will endure as South Korea plays a part in reviving US naval shipbuilding, but South Korean exports will redirect towards China, the EU, and ASEAN in response to 25% US tariffs.
On 4 April 2025, South Korea’s Constitutional Court upheld the National Assembly’s impeachment of President Yoon, officially removing him from office. The decision culminates months of chaos since Yoon abruptly declared martial law on 3 December 2024. Justifying it to eliminate “pro-North Korean anti-state forces”, the move outraged the population and the legislature, as lawmakers from both parties swiftly voted to annul martial law, forcing Yoon to rescind the decree 6 hours after imposing it. By 14 December, the National Assembly impeached Yoon, surpassing the necessary two-thirds majority with the support of 12 PPP members. South Korea now prepares to elect a new leader amid a slowing economy and a volatile global environment.
With Yoon gone, a by-election to replace the President is scheduled for 3 June. Yoon’s downfall was welcomed by the opposition DP, which decisively won the 2024 midterm legislative elections, though a DP presidency is not guaranteed. Their frontrunner is Lee Jae-myung, DP leader and 2022 presidential candidate, who narrowly lost to Yoon by 0.73%. Although the DP base has consolidated around Lee, conservatives view him as a radical firebrand with a litany of criminal investigations from corruption to perjury, though instigated by Yoon’s government prosecutors. Lee’s DP has been criticised as obstructionist, using its legislative control to cause policy gridlock and impeach 22 government officials during Yoon’s term. After Yoon’s impeachment, they impeached acting President Han Duck-soo for refusing to fill vacancies on the Constitutional Court, which the court itself then overturned.
Lee currently leads in polls against potential PPP contenders, though neither party has formally announced a candidate. However, the PPP has gained in polls since the martial law declaration in December 2024. The last time a President was impeached, Park Geun-hye in 2016 for corruption, her conservative Saenuri Party fractured, splitting the right-wing vote in the 2017 election and handing a decisive victory to the DP. The same has not been seen within PPP, which will likely unify behind a single candidate.
The result of the election carries great importance for the trajectory of South Korea’s foreign policy. The PPP is staunchly pro-US, sceptical of China, hawkish on North Korea, and more conciliatory towards Japan. A PPP president, though still hobbled by DP control of the legislature, will likely continue close military coordination with the US and improve cooperation with Japan in combating Chinese and North Korean aggression. The DP seeks to rely less entirely on the US, is dovish on North Korea, and strongly opposes closer ties to Japan over its historical revisionism. Lee has previously mentioned a strong opposition to including Japan in the US-South Korea alliance, and has referred to China as a “strategic cooperative partner”. Particularly in the context of Trump’s 25% tariffs levied against South Korea, Lee may seek a hedging of foreign policy against the US.
The next president will face a difficult economic situation. South Korea’s economy has stagnated amid its political turmoil, achieving just 0.1% real GDP growth across the 4th quarter of 2024. With exports making up 41% of GDP, trade is essential to South Korea’s prosperity. Political uncertainty has dampened business confidence, while the KOSPI stock index and KRW have declined due to US tariffs. South Korea does maintain leverage in trade negotiations with the US: its shipbuilding industry will be useful for Trump’s intentions to expand the US Navy, which has been outgrown by the Chinese Navy in the past decade.
Forecast
Short-term (Now - 3 months)
The presidential election campaign will intensify polarisation and partisanship. The polls between the DP and PPP will likely narrow, increasing policy uncertainty, though a DP victory is slightly more likely.
Medium-term (3-12 months)
The new president will likely seek exemptions from US tariffs. Exports to China will likely increase as producers seek to diversify from the US market.
Long-term (>1 year)
A PPP president will likely struggle to enact their agenda through the DP-controlled legislature as a lame-duck president. A DP president would have much domestic policy leeway, though short of constitutional reform. Regardless, greater strategic hedging against US ties through greater trade with China, ASEAN, and the EU is highly likely.
