AI Boom Mirrors Railway and Dot-Com Eras: Real Tech, Real Bubble Risk

Analysts drawing on historical parallels argue that 'real technology' and 'speculative bubble' are not mutually exclusive — railways and the internet were both transformative and financially ruinous for many early investors. The four largest US hyperscalers are collectively spending hundreds of billions of dollars annually on AI data centres, with capital expenditure revised upward nearly every quarter, mirroring the massive physical infrastructure bets of the railway age. A key concern is that Nvidia, the dominant AI chip supplier, has taken stakes in and provided financing to some of its own largest customers, creating a reflexive loop where chip purchases and valuations reinforce each other rather than reflecting independent outside demand. This dynamic echoes the 1720 South Sea Bubble, in which the company lent buyers money to purchase its own shares, making rising prices appear as validation of the scheme. The more useful question, historians and analysts suggest, is not whether AI is a bubble, but which parts represent durable infrastructure build-out and which parts are speculative financing structures dressed in technological clothing.