Precision equipment manufacturing is hard. It's easy to get round balls, but to get them consistently within a certain tolerance in yields that would beat just

Precision equipment manufacturing is hard. It's easy to get round balls, but to get them consistently within a certain tolerance in yields that would beat just importing them is even harder. I can't find the article now, but I remember reading about the manufacture of a certain kind of high quality lenses and at the time, the place with the highest quality manufacturing capacity was a couple tiny factories in Japan. At some point the technology to make lenses at that quality and yield had been R&D'd in Japan and there it sits. Nobody feels like dumping a few hundred million (or billion) into matching that capability when they can just order them from these places at $20 a pop in volume. "But", people say, "China makes all kinds of high-tech goods!". Sorta, is the answer. China does final assembly on tons of things, but many of the components, ultra-precision parts, are made elsewhere: CPUs, DSPs, Memory, Displays etc. China is getting there as market forces allow, but there often isn't a good reason to try to achieve parity or leapfrog suppliers who you already have good relationships with and who sell you product at reasonable prices.