The US stock market has faced significant declines as President Trump escalates trade tensions with threatened tariffs on several countries. The Dow Jones Industrial Average dropped over 400 points while the S&P 500 pulled back from its record highs. Market sentiment soured as Trump announced 25% tariffs on goods from Japan and South Korea and threatened additional tariffs on Canada. Despite some analysts suggesting markets are becoming desensitized to these tariff threats, the volatility remains evident, with many investors concerned about the potential for an intensified trade war. Economists have warned of potential mistakes from Wall Street amidst this uncertainty, as the markets reflect mixed reactions to the ongoing tariff discussions.