Wall Street Plunges: S&P 500 -4.4%, Nasdaq -5.5% in Worst Day Since April 2025

A sharp AI and semiconductor sell-off hit US equities. The Dow fell 1,833 points (3.44%), the S&P 500 4.36% and the Nasdaq 5.52%, entering correction territory. The Philadelphia Semiconductor Index fell over 12% and Nvidia about 9%. Investors cited fears that Democratic midterm wins could bring restrictions on data center buildout and AI spending.