South Korea's benchmark Korea Composite Stock Price Index (KOSPI) sank below 5,000 points on Friday, 6 November, tumbling more than 8 percent in a sharp sell-off triggered by fears that a Democratic Party sweep in the U.S. midterm elections could slow the construction of artificial intelligence (AI) data centres. The scale of the decline was severe enough to trigger a 20-minute trading halt — the first such suspension in 16 trading sessions.

What Triggered the Crash

The immediate catalyst was a tech rout on Wall Street overnight, where the NASDAQ slumped more than 5 percent after the Democratic Party won gubernatorial control of Texas, a key U.S. state at the centre of AI data centre expansion plans. With Democrats also securing majorities in both the U.S. Senate and the House of Representatives, analysts widely expect the political leverage of U.S. President Donald Trump to diminish considerably in the final two years of his term. That shift in power raised immediate questions about the pace of federally-backed or policy-supported AI infrastructure buildout.

Samsung and SK Hynix Lead Losses

The hardest-hit stocks were Samsung Electronics and SK hynix, which together account for nearly half of the KOSPI's total market capitalisation. Both plunged more than 10 percent in morning trading on Friday, reflecting their deep exposure to AI-related memory chip demand. As global technology firms scale back or recalibrate data centre investments, Korean chipmakers face the most direct earnings risk. This is not the first time KOSPI has reacted sharply to U.S. political shifts, but the magnitude of Friday's move underscored how structurally dependent South Korea's market has become on the AI supply chain.

Fear Index Spikes, Analysts Split

South Korea's stock market fear gauge, the KOSPI 200 Volatility Index (VKOSPI), surged to a three-month high of 64.74 on Friday, according to the Korea Exchange. Analyst Han Ji-young of Kiwoom Securities said volatility in the local market is likely to persist following the sharp decline. However, Lee Kyung-min, an analyst at Daishin Securities, offered a more measured view, stating in a research note that while the Democratic win may prompt delays in AI data centre construction, 'the likelihood of full-scale suspension of such build-out was low.' Daishin Securities described the market's overall reaction as 'excessive.'

Government Response

Finance Minister Lee Hyoung-il convened an emergency meeting with relevant ministers on Friday, pledging swift government intervention. He said authorities 'will preemptively set up measures and take them to prevent our stock markets from excessively responding' to the U.S. tech sell-off. The minister also emphasised that South Korea's economic fundamentals remain solid, even as the government moves to closely monitor external uncertainties. This comes amid broader concern in Asian markets about how a Democrat-controlled U.S. Congress will approach big-tech regulation and AI infrastructure policy going forward.

What to Watch Next

Investors will closely track any policy signals from the new Democrat-majority Congress regarding AI data centre permitting and federal subsidies. Any slowdown in NVIDIA, Microsoft, or Google data centre spending plans would directly impact Korean chip demand. With the VKOSPI at a three-month high and trading circuit breakers already triggered once, further volatility cannot be ruled out until the new U.S. political landscape crystallises.