The US stock market volatility story just turned serious. The Dow Jones fell over 700 points this week. The S&P 500 and Nasdaq are now posting their worst month in 11 months. AI stocks led the collapse. Nvidia crashed despite beating earnings. Big Tech's billion-dollar data center bets are spooking investors. Energy stocks surged 23%. The equal-weight S&P 500 beats the standard index by 6 points this year. Smart money is rotating — fast. Diversify now.