After the U.S. midterm elections, worries about slowing down AI hit global large technology stocks hard, and South Korea’s stock market shut down

After the U.S. midterm elections triggered concerns about a slowdown in the development of artificial intelligence (AI), major U.S. and Asian technology companies lost hundreds of billions of dollars in market value, and global stock markets suffered a sharp sell-off.

As the Democratic candidate who advocated slowing down the development of AI won the election, the stock prices of technology and artificial intelligence-related companies fell sharply.

According to Dow Jones data, the Nasdaq Composite Index, which is dominated by technology stocks, closed down more than 5.5%, evaporating approximately US$2.5 trillion (£1.9 trillion) in market value; other major US stock indexes also experienced significant declines, recording their worst single-day performance since 2025.

The wave of selling also reflects existing concerns in the market about whether the huge amounts of money companies are investing in AI will ultimately pay off.

In Asia, stock market indexes dominated by technology stocks fell sharply in early trading on Friday, and the stock prices of companies that produce chips and related equipment required for AI fell one after another.

Japan's Nikkei 225 index fell 6% in early trading, memory chip manufacturer Kioxia's stock price fell more than 12.6%, and rival Tokyo Electron fell 9.5%.

South Korean chipmaker SK Hynix fell more than 11.5%, and Samsung Electronics fell nearly 10%.

The sell-off in the Seoul stock market caused the South Korea Composite Stock Price Index (Kospi) to plunge more than 8.5% and triggered the so-called "circuit breaker", which suspends trading to curb panic selling.

Taiwan's weighted stock price index (Taiex) fell more than 8.3%, and wafer foundry leader Taiwan Semiconductor Manufacturing Co. (TSMC) fell nearly 8.5%.

MarketWatch chip industry analyst Britney. Britney Nguyen, a business analyst, said this reflects market concerns about the scale of AI infrastructure spending that “continue to ferment.”

Data center pressure

Democratic candidates have advocated slowing the expansion of the data center and artificial intelligence industries in many elections across the country, and dozens of proposals aimed at limiting the development of such infrastructure have appeared on ballots across the country.

With Democrats taking control of the Senate and House of Representatives in Tuesday's midterm elections, they will dominate Congress for the remainder of Donald Trump's term.

The newly elected Democratic governor of Texas, Gina Hinojosa, strongly opposed data center expansion during the campaign and promised to suspend approval of new data center construction projects.

Trump took to social media to blame political opponents for the stock market crash.

"The stock market had one of the worst days in history because of the election results," he wrote.

And, "Remember, it's not the Republicans, it's the Dumocrats. But don't be afraid, no matter what, we will soon be stronger than ever. Make America Great Again!"

Some Democrats believe that the artificial intelligence industry is developing too fast without adequate supervision and safety protection measures, and therefore hope to use the new power of Congress to restrict it.

Democratic Senator Bernie Sanders posted a message on the

Wall Street hits 'new wave of panic'

The stock prices of companies that rely heavily on AI data center business, including key chip manufacturers and semiconductor companies, plummeted on Thursday, highlighting that investor concerns have been gradually accumulating.

During Thursday's trading session in European stock markets, chip manufacturer Infineon's share price fell more than 8.5%, and technology equipment manufacturer ASML fell 6.5%.

Nvidia shares fell more than 9%, wiping out more than $400 billion in market value.

Other chip manufacturers also suffered setbacks, with AMD and Micron both falling more than 17%; Intel falling 10.3%; and memory card manufacturer Sandisk plummeting more than 22%.

The Philadelphia Semiconductor Index, which tracks the performance of 30 large semiconductor companies, fell more than 12%.

The stock prices of Elon Musk's SpaceX and Tesla also fell sharply, falling 8% and nearly 11% respectively, with a combined market value of more than US$300 billion evaporated in a single day.

Musk had previously invested nearly $450 million in support of Republican candidates, including at least $45 million to help Ken Paxton run for the Texas Senate seat. However, Texas still turned to support the Democratic Party on Tuesday night due to the so-called "Democratic tsunami".

Overall, the so-called "Magnificent Seven" (Magnificent Seven), including Apple, Huida and Tesla, have lost approximately US$1 trillion in market value in a single day.

The decline also spread to other major U.S. stock market indexes.

The S&P 500 closed down 4.4%; the Dow Jones Industrial Average gave up all of Wednesday's gains and closed down more than 3.4%.

Due to the excessive decline, the Nasdaq Composite has entered what market participants call "correction territory" (correction territory), which means that the index has fallen by at least 10% from its recent high.

Susannah Streeter, chief investment strategist at Wealth Club, said that the sharp declines in the Nasdaq and S&P 500 are sending shock waves to global markets.

She pointed out: "A new wave of panic surrounding AI investment has hit Wall Street hard."

"The market was originally worried that the huge amount of money invested in AI infrastructure may not bring the returns expected by investors. Now it is facing the risk that data center construction may slow down significantly. Two worries broke out at the same time."

Charu Chanana, chief investment strategist at Saxo Bank, said that data center approvals will be subject to more stringent scrutiny in the future, and its impact on the environment and electricity prices may also delay project progress and push up overall industry costs.

She said that both major political parties want to ensure that the United States maintains its leadership in science and technology, "but supporting the development of AI and allowing the unrestricted expansion of infrastructure at any cost are two different things."

Some tech industry leaders said they were surprised by the scale of anti-data center sentiment this midterm election.

Greg Brockman, president and co-founder of OpenAI, said he believes everyone has been surprised by society's response to data centers, and that the industry still needs to do more to win local community support.

"What we've come to realize over the past year is that when you're in San Francisco and you want to build infrastructure in Texas, Georgia and other places, you can't just post on social media and say, 'This would be a good thing,'" Brockman said Wednesday night at the WSJ Tech conference in Napa, Calif. "You have to actually get out into those communities."

Meta President Dina Powell McCormick said that the technology industry needs to work harder to explain the value of AI to the public.