Citation on "impossible"? Under Tim, Apple has invested $100 million in US manufacturing. The Mac Pro has been manufactured in Austin since 2013.
Secondly, a $100 million investment in manufacturing is not a small number. Unless you are Apple. Let's assume a wildly low profit margin on the average iPhone of $250. Apple would have to sell 400,000 iPhones to cover that investment with pure profit. In 2017, Apple sold 216,760,000 iPhones.
You probably read comments that were Tesla be made by an established player, it would've been made for half the cost?
Tesla's success slash failure is thanks to that absence of the established manufacturing culture in light industries.
USA is still is a big manufacturing country, it's curse is that their industry manufacturers "invisible goods," and that its companies are low profile.
For examples, almost all "picoprobes" in the world are made by one small company in USA that you can't even google.
On the other hand, even a third tier smartphone maker in China has high media profile, and every highschooler will be able to name a few.
Electronics is one of the most automated industries on the planet already. You can run in anywhere you want where you can put an SMT line. There are electronics factories even in African countries.
What matters is being able to run in cheaper and better than the next competitor, and you can't do it with three quarters of the global electronics manufacturing ecosystem sitting in a single city - Shenzhen.
IF Apple will agree to sell their products at less than triple digits markup, than they will be free to make iPhone in America.
You are ignoring your own argument by explaining that every car manufacturers wants to produce as cheap as possible, which is also the same reason why Tesla wants to automate everything.
The original comment/question was: how can Tesla do it and not Apple.
Ps. The price of a Tesla is actually okay. It's not 100k and it's avg market priced. iPhone was never avg market priced