Stock market today: Dow, S&P 500, Nasdaq smoked as Powell warns of 'challenging' tariff impact, Nvidia plunges
Stock market today: Dow, S&P 500, Nasdaq smoked as Powell warns of 'challenging' tariff impact, Nvidia plunges

US stocks fell after Nvidia revealed costly new curbs on chip exports to China, and investors grappled with uncertainty over President Trump's trade policy.
