You've never read a history book.
So are you one of those "citizens of the world"? I'm not, I am a US citizen and screw the rest of the world.
Every founding father was a protectionist and things are worse now than at that time.
If US company wants access to the US market with off shored slave labor produced products then they should have to pay a tariff. A 10% tariff out to balance things out. They can decide whether to pass that cost on to their customer or not. Pres. Washington would approve...
Tariffs applied only to things we were producing ourselves. NOT to things we were NOT, and could not be, producing. Read your history books.
Now, as to your "slave labor" canard. Every person who works on the Apple assembly lines is a person who stood in line to apply for the job and was selected out of thousands who applied. They are paid wages that are seven times the countries minimum wage. . . and THREE times the standard wage for people working on non-Apple products. They are there by choice. They are not SLAVES.
Apple is doing everything it can to stop the use of what are termed "Conflict Minerals" that are associated with slave and child labor, most of which comes out of Muslim Africa, and use only certified raw materials. This is an almost intractable problem for some metals, as one ingot may be indistinguishable from another after smelting and the end buyers are at the mercy of the ethical behavior the upline. Apple has staff whose only duty is to follow the trail upline and change unethical practices when they find them. As far as i know, no other company is doing this.
Even if manufacturing were brought back to the US, these problems would persist.