Silicon Valley: Not Enough Of A Good Thing:

The right questions to be asking aren’t “why does Silicon Valley create so few jobs;” it’s “why doesn’t everyone move to the Bay Area” (the rent is too damn high) or “how come there’s only one high-tech cluster.” After all, if industrial age capitalism had just created the prosperity of the Detroit area in its heyday, we’d look on it as a huge bust. But we had lots of industrial production clusters, of which the Detroit automobile industry was just the most famous.

I think there’s a standard geographical reason why capital intensive production of material goods exhibits polycentrism: the cost of transport matters. Many of the early industrial nuclei were located relatively close to the inputs for manufacturing. Additionally, once the goods were produced they had to be distributed as cheaply as possible, so location was another essential fixed parameter. Big eastern industrial centers loom large in the public imagination, but the same logic applies in other regions of the nation. Cheap electricity and abundant clean water is why many tech-oriented manufacturers are based out of the Pacific Northwest. It isn’t as if you could just relocate the Columbia river.