Just three companies now account for approximately 21% of the S&P 500's total market capitalization. NVIDIA (NVDA), Apple (AAPL), and Microsoft (MSFT) have become so dominant that their performance could determine the direction of the entire stock market. But what happens if these technology giants stumble? In this episode, 24/7 Wall St. co-founder Doug McIntyre and senior writer Lee Jackson discuss the extraordinary concentration of the S&P 500 and why millions of investors may be taking on more risk than they realize. Much of today's market enthusiasm is driven by artificial intelligence. Companies like NVIDIA, Microsoft, Alphabet (GOOGL), Amazon (AMZN), and Meta Platforms (META) have benefited from enormous expectations for AI growth. But Doug and Lee identify several potential threats to that optimism. They explore how cheaper open-source AI models could challenge industry leaders, why opposition to AI data center construction threatens expansion plans, and how growing electricity ...