why us stock market been weak and volatile for months while Europe stock market keep reaching new highs?

The U.S. stock market has experienced volatility in early 2026 due to high valuations, AI return concerns, and a shifting macro backdrop, while European markets have hit record highs, driven by strong corporate earnings, increased defense spending, and a catch-up in valuation. The U.S. has faced pressure from a potential shift in trade policy, while European, especially defensive and value-oriented sectors, benefited from a less expensive, more stable, and, in some cases, weaker-dollar environment