Pittsburgh
Three rivers made it strategic (1758), coal made it Steel City (25% of global output), collapse unmade it (150,000 jobs lost), and CMU remade it ($658B in startup value).
Pittsburgh exists because three rivers meet here—and whoever controlled that junction controlled the Ohio Valley. In 1754, the French built Fort Duquesne at the confluence of the Allegheny and Monongahela rivers. When British General Forbes captured it in 1758, he renamed it for Secretary of State William Pitt. The strategic logic was simple: rivers were highways, and this was the continent's most important intersection.
That same confluence of waterways made Pittsburgh ideal for heavy industry. Coal from nearby mountains, iron ore via the Great Lakes, and water transport in every direction. Andrew Carnegie, a Scottish immigrant who'd worked his way up through railroads, recognized the opportunity. After witnessing the Bessemer process in Britain, he opened the J. Edgar Thomson Steel Works in 1875. By the 1880s, Carnegie Steel produced 25% of global steel output. In 1901, he sold to J.P. Morgan, creating U.S. Steel—the world's first billion-dollar corporation. At its peak, Allegheny County produced 24% of American pig iron and 44% of open hearth steel.
The collapse, when it came, was devastating. Japanese and Korean mills with newer technology undercut American prices. The 1981-82 recession gutted what remained. Nearly 150,000 steelworkers lost jobs. Unemployment hit 17% in 1983. The Homestead Works, which had employed 15,000, closed in 1986. Population dropped 8% in a decade. Pittsburgh should have become another rust belt cautionary tale.
Instead, the city built a second economy on top of the first. Carnegie Mellon University, ranked first globally for AI and machine learning, has generated $658 billion in startup value. The university's annual economic impact across Pennsylvania surged by $600 million since 2016. UPMC grew into one of America's largest healthcare systems. Today the metro employs 37,580 technology workers. Amazon pledged $20 billion for regional data centers. Defense robotics spending is projected at $41 billion for 2020-2025.
By 2026, Pittsburgh aims for 100,000 tech jobs through its AI Strike Team initiative. The city that made Carnegie's fortune now makes Uber's self-driving cars. The confluence that once shipped steel now exports algorithms.