Massive AI and cloud infrastructure spending by tech giants is flooding the market with new debt. For the first time since the 2008 crisis, this oversupply, not macroeconomic fears, is becoming a primary driver of market volatility and repricing risk for existing corporate bonds.

Before AI delivers long-term deflationary productivity, it requires a massive, inflationary build-out of physical infrastructure. This makes sectors like utilities, pipelines, and energy infrastructure a timely hedge against inflation and a diversifier away from concentrated tech bets.

The massive capital expenditure in AI infrastructure is analogous to the fiber optic cable buildout during the dot-com bubble. While eventually beneficial to the economy, it may create about a decade of excess, dormant infrastructure before traffic and use cases catch up, posing a risk to equity valuations.

While the current AI phase is all about capital spending, a future catalyst for a downturn will emerge when the depreciation and amortization schedules for this hardware kick in. Unlike long-lasting infrastructure like railroads, short-term tech assets will create a significant financial drag in a few years.

The massive capital rush into AI infrastructure mirrors past tech cycles where excess capacity was built, leading to unprofitable projects. While large tech firms can absorb losses, the standalone projects and their supplier ecosystems (power, materials) are at risk if anticipated demand doesn't materialize.

The massive spending on AI infrastructure may be a form of 'malinvestment,' similar to the telecom buildout during the dot-com boom. Rajan warns that while AI's promise is real, the transition from infrastructure creation to widespread, profitable use could be slow, creating a valuation gap and risk of a market correction.

The current AI investment boom is focused on massive infrastructure build-outs. A counterintuitive threat to this trade is not that AI fails, but that it becomes more compute-efficient. This would reduce infrastructure demand, deflating the hardware bubble even as AI proves economically valuable.

Unlike railroads or telecom, where infrastructure lasts for decades, the core of AI infrastructure—semiconductor chips—becomes obsolete every 3-4 years. This creates a cycle of massive, recurring capital expenditure to maintain data centers, fundamentally changing the long-term ROI calculation for the AI arms race.

Unlike the railroad or fiber optic booms which created assets with multi-decade utility, today's AI infrastructure investment is in chips with a short useful life. Because they become obsolete quickly due to efficiency gains, they're more like perishable goods ('bananas') than permanent infrastructure, changing the long-term value calculation of this capex cycle.