They are just assembling them according to quality control set by Apple. Electronic components for them are usually imported from outside.
Their knock-off copy of Russian war planes are not doing well either.
Un, nope.
The components are made in China too for the most part. The Chinese ARE making the iphones and have been doing so for a long time.
Partly explains Apple's super high, insane profits.
You are living in cloud cuckooland.
Read this and weep;
China Hypersonic Missile Test Showed Unprecedented Capability: FT