The great artificial intelligence mania that has inflated stock valuations to dizzying heights is showing unmistakable signs of strain. After a relentless 18-month rally that saw the Nasdaq Composite soar more than 60%, the air is leaking from the tyres. This week alone, the tech-heavy index has shed over 4%, with AI bellwethers like Nvidia, Microsoft, and Alphabet taking the brunt of the selling. The question now is not whether this bubble will burst, but when – and how much collateral damage it will inflict on the broader market.
Let’s cut through the hype. The AI trade was always a story of promise rather than profit. Nvidia’s market capitalisation briefly touched $3 trillion, making it more valuable than the entire UK stock market. Yet its price-to-earnings ratio hovered around 70, a level that would make even a dot-com speculator blush. The justification? That AI would revolutionise everything, from healthcare to defence. But revolutions take time, and markets have a nasty habit of discounting the future too aggressively.
Central banks are not helping. The Federal Reserve has signalled it will keep rates higher for longer, a death knell for speculative assets that thrive on cheap money. The yield on the 10-year US Treasury has climbed to 4.5%, offering a risk-free alternative that looks increasingly tempting compared to overpriced equities. Capital is beginning to rotate out of growth stocks and into defensive sectors. The rotation has started, and it is not orderly.
Look at the options market. The put-call ratio on the QQQ, the Nasdaq tracker, has spiked to a 12-month high, indicating a wall of worry. Hedge funds are piling into protective puts, a classic sign of institutional skittishness. Meanwhile, retail investors, late to the party, are still buying the dip. That is usually the final act before the curtain falls.
The parallels with the 2000 dot-com bubble are hard to ignore. Then, as now, investors chased any company with a .com suffix. Today, they chase any stock with an AI narrative. Remember when Palantir Technologies, a data analytics firm with a modest revenue base, was valued at over $50bn? The market is rewarding stories, not earnings. That always ends in tears.
Fiscal responsibility is another concern. Governments, particularly in the US and Europe, are pouring billions into AI subsidies and tax breaks. This is corporate welfare dressed up as industrial policy. It distorts capital allocation and creates a moral hazard: firms chase grants rather than genuine innovation. The market is finally waking up to this reality.
What next? A correction of 20% to 30% in the Nasdaq is entirely possible. That would wipe out trillions in paper wealth and ripple through pension funds and 401(k)s. The Bank of England and the ECB will watch nervously, but they have limited ammunition. Inflation is still above target, so rate cuts are off the table for now.
For the savvy investor, this is a time for caution, not courage. Reduce exposure to high-beta tech. Increase cash allocations. Gilt yields offer a decent real return for the first time in years. The bubble is not bursting today, but the cracks are visible. When it does, those who have prepared will sleep better.
