S&P 500 edges up as tech steadies; Dow sinks nearly 500 points amid UnitedHealth scrutiny

US stocks displayed a mixed performance as tech and growth stocks saw a cautious return, while healthcare sector weakness impacted the Dow. Global markets reacted to potential ECB rate cuts and escalating tensions between President Trump and the Federal Reserve. Asian markets closed higher, contrasting with declines in European indices amid ongoing trade and monetary policy uncertainties.