Philadelphia Semiconductor Index drops 9.75% as $3 trillion vanishes

The drop came a day late. On Wednesday the Dow rose 1,569 points, or 3%, its best performance after a midterm election in 44 years, and the S&P 500 rose 1.6% to 7,688.62 as oil fell more than 8%. But the midterm risk to AI was already showing up in parts of the market that day: Vistra plunged 14% and Vertiv fell 13% on fears of data center moratoriums, while Nvidia slipped only 3%. Smaller AI cloud providers such as CoreWeave were also hit hard, since a permitting slowdown in Texas would hurt operators like CoreWeave before it reached the hyperscalers that are their main customers. Meanwhile, some of the biggest tech companies, which pay for the build-out, saw their stocks rise. Some analysts and economists argued political pushback could let air out of an inevitable AI bubble without popping it. The selling then spread overnight: South Korea's Kospi closed down 5.28% with trading halts during the session, Taiwan's main index fell 3.2% and the Nikkei 1.79%. Even so, four of the S&P 500's 11 sectors were up on the day, including consumer staples, which rose 1.5%, and Berkshire Hathaway hit an all-time high.