Investors are still betting on AI, but doubts are piling up

In today’s CEO Daily: The AI consensus is starting to crack.

The big leadership story: The race to fix major security flaws.

The markets: Down globally as oil rises and investors weigh Meta and Tesla earnings.

Plus: All the news and watercooler chat from Fortune.

Good morning. For years, investors in both public and private markets have had one answer to almost every question: AI. About two-thirds of S&P 500 returns since 2024 have come from 42 AI stocks and almost all of the venture dollars this year are flowing into AI, with some firms nearing trillion-dollar valuations. The consensus may be starting to crack amid worries about valuations, financing, infrastructure costs, and the speed of adoption. In speaking with investors at Alpha Partners’ AlphaMarket 2026 conference yesterday, I heard themes that reinforce what business leaders are also telling me.

The short-term risks are real. Former Defense Secretary Donald Rumsfeld used to talk about the known knowns, the known unknowns and the unknown unknowns. The first category is what we know to be true: from America’s aging workforce and rising debt to the transformative potential of AI. The last includes those black-swan events that come out of left field and test a company’s resilience, from war to pandemics. But the middle category is where investors play the odds when it comes to risks. They know that the AI boom is being financed on borrowed money, with circular financing deals that only add to the fog. They know the buildout is expensive and could take decades to pay off; that wild swings in revenue estimates and reports of rogue AI are red flags. And companies like CoreWeave can’t rack up $52 billion in liabilities without a clear path to pay it back. A good long-term bet can be derailed by the reality........

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