How is it that you accept that 'colocation theory' explains Silicon Valley, but you dismiss it as explaining Shenzhen without explaining why one is different from the other?
Shenzhen can also produce that supply chain, but they are no more capable than a lot of American cities.
What Shenzhen has that America doesn't are cheap labor, and a devalued currency.
Silicon Valley is different primarily because there is no other city with the concentration of brilliant engineers vs others. NYC for example probably has more computer engineers by numbers, but there are more opportunities for those engineers to make huge pay in other industries outside of startups. The fact that Silicon Valley is full of amazing engineers who are excited to work in the tech industry means that it is the best location for your startup to locate (relatively, and if you need a lot of engineers, not all startups do, some need more sales focused or science focus etc and there are better cities for those companies).
Citation needed. There's a huge number of companies making memory, displays, batteries, CPUs at scale in the midwest? Who are they currently selling their products to? I admit to being very ignorant of such firms.
What we do know is that Intel has a fab in Arizona for example and Corning's headquarters (gorilla glass) are in NY etc.
I also don't know for sure what is in each city in China. While it is public information (for the most part), finding a source to back my claim would be as possible as backing the authors claim.
The author says that the reason Apple can manufacture there more profitably is because of colocation of other industries.
I say that while colocation may be a factor, the real factor is a devalued currency which the author completely overlooks.
The expertise, density and investment levels are totally different and cannot be rapidly changed.
I'll go as far to say that a devalued currency and/or cheap labor may have been the reason the manufacturing base moved initially, but technology has advanced since that time and Shenzhen has now built up an infrastructure advantage which is much harder to counter.
Do you have a source for that? Foxconn has greater than 1 million employees. I don't think there is any company with a labor force of that scale in the US, or anywhere else in the world. And, per the article at the top of this thread, the bigger issue is the supply chain. If iPhones were made in the Midwest, they would still be importing glass, simple hardware, and thousands of other parts that are still made in China.