Has the US stock market been hijacked by AI? According to data from @KobeissiLetter: Since 2026, the S&P 500 has gained a net $5 trillion in market value, with AI stocks alone contributing $6 trillion. Energy added $200 billion, while other sectors actually dropped $1 trillion. At the start of 2023, AI stocks made up about 27% of the S&P 500's market value. Now, it's 47%. In other words, AI is practically half of the US stock market. Is this a trend? FOMO? Or a bubble?