Will data centers crash the economy?

Noah Smith argues that the AI data-center buildout is now a major source of economic growth, but that its financing mix matters more than the boom itself. He compares it with earlier infrastructure booms and busts, then asks whether today’s lending structure could turn a capex slowdown into broader financial stress.

Reading notes

#

• AI data centers are absorbing very large amounts of capital, and that spending is helping U.S. growth even as other parts of the economy look weak.
• The spending boom is concentrated in Google, Meta, Microsoft, and Amazon, with capex taking up a very large share of sales for some of them.
• Earlier infrastructure booms, such as railroads and telecom, also went too far before demand caught up, and the result was a crash.
• A data-center bust would hurt Big Tech shareholders and reduce investment, but the deeper risk is a financial crisis if the spending is debt-financed.
• Historical work on bubbles suggests that leverage and credit growth make crashes more dangerous for the real economy.
• The key question is who is lending to the AI buildout, not just how much is being spent.
• Some funding comes from internal cash flow, equity, and bonds, which look less threatening at the macro level.
• The more worrying channel is private credit, which has grown quickly and is increasingly tied to bank lending.
• Banks’ lending to private credit funds has risen sharply, and bank exposure could also come through bonds backed by private-credit debt.
• The Boston Fed warns that banks are more exposed to the private-credit market than before and that tail risk may be underestimated.
• If many private-credit loans are tied to data centers, defaults could be highly correlated in an AI downturn.
• Life insurers are also increasingly exposed to below-investment-grade debt through private credit, adding another possible transmission channel.
• Smith ends by listing the ingredients that make a financial crisis more plausible: a powerful “this time is different” story, rising debt concentrated in one sector, an opaque and fast-growing credit market, and lenders that matter to the wider system.