The AI economy is being constrained by the physical world: The Iran war threatens to squeeze the industrial inputs that chip manufacturers depend on, the latest confirmation that once-reliable global chokepoints are now more fragile than ever. Why it matters: It is part of a growing pattern defining the economic conditions of the 2020s: shocks exposing the fragility of supply chains that the world took for granted. The AI buildout is the latest to be throttled by this trend — in this case, the effects of an uncertain Middle East conflict and the Strait of Hormuz's effective closure. What they're saying: "Hyperscalers are committing roughly $650 billion to U.S. AI infrastructure this year alone. And that investment assumes the supply chain holding it together remains intact," Moody's David Pan tells Axios. "The AI economy runs on tokens, tokens run on GPUs and GPUs depend on Qatari helium, Israeli bromine, and [liquefied natural gas] tankers with a single, 21-mile-wide exit from the Persian Gulf," Pan adds.…