U.S. stock markets are experiencing significant fluctuations as uncertainties surrounding new tariffs imposed by former President Trump weigh heavily on investor sentiment. The S&P 500 has notably snapped its longest winning streak in 20 years, while both the Dow and Nasdaq have also closed lower amidst wavering trade hopes. Analysts are closely monitoring the upcoming Federal Reserve meeting, which is expected to impact market direction. With major indices dipping in response to trade risks and oil price fluctuations, investors remain cautious as they await further developments on tariff negotiations and economic indicators.