How does President Trump know what each American needs?
We each decide that when we buy ... or abstain from buying. 
Discussion
That's not quite right though is it? You may require a type of thing but not necessarily a specific thing.
Wants & needs aren't really the same thing, parts for something you already have perhaps.
Whether the method is ethical or not, you still need to produce things at home, no matter how much some politicians preach a "service economy".