Advanced electronics manufacturing never left the US. The problem is that all the consumer-grade stuff left, and what's left is all really high-end military stuff, and is stupidly expensive. It's great if you're a defense contractor building some state-of-the-art weapons system that really needs the performance offered by those process technologies, but if you want to build a simple prototype for your small business, or you want to build some not-so-cutting-edge electronics in high volume for consumers, it just isn't feasible.