Billions are being invested in AI infrastructure through loans and private credit, fueling a potential bubble amid warnings from industry leaders about overinvestment and long-term sustainability risks, reminiscent of the dot-com bubble.
Despite concerns of a bubble, historical analysis suggests that US stocks are not in a bubble, as the S&P 500's performance over the past three years has been relatively modest compared to previous bubble peaks. However, extreme bullishness in investor sentiment and the market's heavy reliance on a few large companies raise caution. While the market has become more concentrated, the recent retreat in stock prices tempers the extreme nature of the situation. U.S. stocks have seen a strong start in 2024, with the S&P 500 and Nasdaq Composite posting gains, but caution remains amidst record highs and extreme bullishness.