US stock indexes recently hit fresh highs driven by artificial intelligence, pushing many tech market caps sharply higher and intensifying debate over an 'AI bubble'. Market participants say the rally's durability depends on sustained AI build-out, c

2026-06-02

US stock indexes recently hit fresh highs driven by artificial intelligence, pushing many tech market caps sharply higher and intensifying debate over an 'AI bubble'. Market participants say the rally's durability depends on sustained AI build-out, corporate profitability and macro fundamentals; a US slowdown that curbs corporate spending on AI infrastructure is a clear downside risk. Several strategists say the market lacks classic end-of-bull triggers—widespread speculative mania, broad margin deterioration or renewed Fed rate hikes—but elevated valuations, concentrated gains and very high earnings expectations leave the AI-driven rally in a fragile boom.