When the stock market has a very bad day, the search for a culprit begins immediately. On Thursday, President Donald Trump had his answer ready: it was the Democrats.

The market had just endured a brutal session. About $3 trillion was wiped off the S&P 500, and the Nasdaq 100 logged its worst day since the 2020 pandemic. The trigger, at least in the political telling, was the midterm elections, a day after Democrats secured control of Congress.

Trump Says 401(k)s Have Dropped

In a post on Truth Social, Trump said the stock market "suffered one of the Worst Days in History based on the results of the Election."

"Such a sad thing to watch!" he said. "Your 401(k)s have, therefore, dropped. Remember, it wasn't Republicans, it was Dumocrats."

He didn't stop at the blame game. "Do not fear, however," Trump said, adding that "we will soon, one way or the other, be BIGGER AND STRONGER THAN EVER BEFORE."

Chip Stocks Lead the Slide

The numbers behind the selloff were ugly across the board. The State Street Technology Select Sector SPDR ETF (NYSE: XLK) closed 8% lower on Thursday, while the VanEck Semiconductor ETF (NASDAQ: SMH) sank 11.21%.

AI bellwether Nvidia Corp. (NASDAQ: NVDA) fell nearly 9.26% in regular trading. Advanced Micro Devices Inc. (NASDAQ: AMD) slumped 17.26%, and Micron Technology Inc. (NASDAQ: MU) fell 17.46%.

Elon Musk's Tesla Inc. (NASDAQ: TSLA) and Space Exploration Technologies Corp. (NASDAQ: SPCX) fell 10.77% and 9.05%, respectively.

Then, as often happens after a panic, the overnight session offered a bit of relief. Nvidia was up 1.36%, AMD up 3.57%, and Micron up 3.42%. Tesla gained 0.78%, while SpaceX was up 2.24%.

Context matters here: the drop came a day after Wall Street celebrated a historic post-election rally. Markets, it turns out, are not always known for consistency.

Data Center Bans Pile Up as Democrats Push for a Halt

Beyond the political blame, there was a concrete policy worry driving the tech selloff. Democrats' midterm win raised fears of tougher data center restrictions, and Sen. Bernie Sanders (I-Vt.) used the moment Wednesday to renew his call for a national moratorium.

The trend was already building before the election. Citi Research data shared by The Information shows U.S. data center bans and pauses rose from near zero through mid-2025 to more than 500 by October.

That's a lot of local resistance for an industry that has been spending heavily on AI infrastructure. If data centers become harder to build, the companies that make the chips powering them start to look a little less unstoppable.

Price Action: The State Street SPDR S&P 500 ETF Trust (NYSE: SPY) fell 4.41% to close at $733 on Thursday and rose 0.25% to $734.81 in extended trading. The Invesco QQQ Trust (NASDAQ: QQQ) fell 6.49% to $647.05 and rose 0.83% to $652.43 in after-hours trading.

Market data rankings indicate the State Street ETF has a Momentum score in the 65th percentile and a negative short-term price trend. Over the medium and long term, the ETF has a positive trend.

Disclaimer: This content was partially produced with the help of AI tools and was reviewed and published by MarketDash editors.