As a non-american, I think diversifying and spreading the production (and knowhow) of technology is a good thing, in pretty much the same way not having only one browser/os vendor is a good thing. It's even better when it's spread geographically, and across different cultures.
I understand the reasoning of wanting to keep every thing local, but, and please pardon my frankness, it seems selfish .
It's the centralisation in Shenzhen that, while awesome in one way, is the most troubling to me. If "something", be it politics or natural disaster, or crazy madman, happens to the wrong part of Shenzhen, the global impact would be dramatic.
Remember a bit over a decade ago, when earthquakes on Taiwan sent RAM prices soaring? Or when flooding in South Asia sent harddisk prices through the roof not that long ago?
The centralisation in Shenzhen is rapidly becoming a far higher risk to the global economy than either of those two.