Wall Street’s AI Bet Drives Market, Debt and GDP Risk

Axios reports that AI spending has become so dominant that it is concentrating U.S. stocks, corporate debt, private credit and even GDP growth around a single, unproven trade, raising the stakes if monetization falls short. UBS estimates hyperscale data‑center operators could spend up to $700 billion from their balance sheets on AI this year, while tech companies are projected to issue more than $1 trillion in new debt to fund those ambitions, with Morgan Stanley expecting private credit to cover roughly half of a $1.5 trillion data‑center buildout. The eight largest publicly traded U.S. tech companies with AI ambitions now make up nearly half the S&P 500, and JPMorgan calculates that AI‑linked names produced about 70% of the index’s 2025 gains, while Harvard’s Jason Furman says AI capital spending alone drove over 90% of U.S. economic growth in the first half of 2025. The piece spotlights Anthropic’s eye‑popping $380 billion valuation and $14 billion revenue run rate, even as CEO Dario Amodei warns that next‑generation models could eventually cost up to $100 billion to train, raising doubts about whether revenues can outrun compute costs. Moody’s cautions that as private‑credit exposure to AI bleeds into banks, insurers and retail products, a sharp AI repricing could ripple across the financial system, yet market participants tell Axios they remain eager to pile in, struggling to find ways to diversify away from the AI trade. For U.S. investors and policymakers, the article underscores that AI has shifted from a tech‑sector story to a systemic concentration risk in equity markets, credit markets and the real economy.