Trump’s 2026 Bull Market is Really Just an Nvidia Rally

The article argues that the 2026 U.S. market rally is highly concentrated in Nvidia (NVDA.OQ), which has become so large it’s effectively driving the S&P 500’s gains. With a market value of roughly $5.2 trillion and a ~15% year-to-date rise, Nvidia alone accounts for about 20% of the S&P 500’s ~9% YTD gain. Broader market breadth is weak: only 57% of S&P components are positive this year and 61% are underperforming the index, with the smallest decile down roughly 23% YTD versus +7.8% for the largest decile. The piece warns that this concentration masks underlying economic and inflationary concerns and that a stumble in Nvidia could expose the rally’s fragility, urging investors to recognize index-weighting risks when buying broad funds.