Historical data shows that when CapEx for a new technology exceeds 2-3% of GDP, a market crash follows within a few years. Today's AI infrastructure spending has reached similar levels, with 93% of GDP growth coming from AI CapEx, suggesting the current tech boom is unsustainable and headed for a correction.

Today's massive AI company valuations are based on market sentiment ("vibes") and debt-fueled speculation, not fundamentals, just like the 1999 internet bubble. The market will likely crash when confidence breaks, long before AI's full potential is realized, wiping out many companies but creating immense wealth for those holding the survivors.

The imminent IPOs of giants like SpaceX and OpenAI will force investors to sell existing holdings to raise cash. This supply shock will likely target the overextended semiconductor and large-cap tech sectors, potentially marking a relative performance top for the Nasdaq as liquidity is reallocated to new issues.

Warren Buffett's market indicator, comparing total stock market valuation to GDP, is now over 200%. This far exceeds the 150% peak during the dot-com bubble, suggesting the entire market is in historically overvalued territory. This amplifies the systemic risk of a potential AI-led correction.

The market rally is concentrated in AI stocks dependent on a massive infrastructure build-out. Historically, such capital-intensive ventures, like railroads and the internet, often cause widespread bankruptcies when revenue fails to grow fast enough to cover costs.

The CAPE ratio has crossed 40 for only the third time in 150 years. The previous two instances were immediately before the 1929 Great Depression and the 1999 dot-com bust, suggesting extremely negative 10-year returns for stocks.

A key indicator of a bubble's final stage, observed only four times in U.S. history (1929, 1972, 2000, 2021), is when speculative, high-beta stocks that led the rally start to fall sharply while blue-chip indices continue to grind higher. This market divergence is a 'primal scream' that a crash is imminent.

A market enters a bubble when its price, in real terms, exceeds its long-term trend by two standard deviations. Historically, this signals a period of further gains, but these "in-bubble" profits are almost always given back in the subsequent crash, making it a predictable trap.

The CAPE ratio, which compares stock prices to average 10-year earnings, is at a level seen only twice before in history: just before the 1929 Great Depression and the 1999 dot-com bubble. This indicates a severely overvalued market ripe for a major correction.