Throughout the Midwest, there are excellent research universities, large industrial manufacturers, and smart hardworking people.
It would be folly to try and relocate existing expertise into a concentrated area already struggling with crowding.
China concentrated growth near the oceans because it's rivers were rather wild and dangerous. Also the farther you go west in China, the more rugged and desert like the country is.
Meanwhile the US has two different coasts. It also has a central portion with a river that is good for transport of goods. This as you say, decentralizes the country and massively lowers the risk of any one event knocking manufacturing out in the country.