The AI build-out is on track to become the biggest economic bet in U.S. history, dwarfing the investments made to fund other huge U.S. infrastructure projects such as the railroads, the highway system and the plumbing for the internet.  Total investment in data centers and related artificial-intelligence infrastructure is projected to total $10.3 trillion from 2025 to 2032, according to new estimates by economist Stijn van Nieuwerburgh published by the Brookings Institution. That is a staggering 3.6% of gross domestic product a year, on average. Never before has the U.S. economy been so dependent on the build-out of a single…