Wall Street's worst day in 18 months as tech stocks plunge on AI fears

Wall Street suffered its worst day in over a year and a half on Thursday, with tech stocks plunging on fears that the Democratic election victory will slow artificial intelligence development. The S&P 500 fell 4.4 percent and the Nasdaq dropped 5.5 percent. Investors worry Democrats, who won big in the midterms, will restrict data center construction, a key driver of AI growth. They also gained governorships in states like Texas and Georgia where such centers are planned. Nvidia lost 9 percent and AMD 17 percent, erasing $2.5 trillion in market value from the top 100 Nasdaq companies. The losses follow Wednesday's gains driven by hopes the election result would ease oil prices. Elon Musk's Tesla and SpaceX fell 11 and 9 percent, adding to his political setback, as a Democratic Congress may scrutinize his businesses and complicate a potential Tesla-SpaceX merger.