By providing subsidies, you make it cheaper to build things in the US, so people do. It’s the reason we have so much farming, even though it’d be cheaper to outsource that.

By shutting down international trade, we will build things in the US where it’s affordable, and where it’s not we just do without.

Point is, you won’t get an iPhone anymore. You likely won’t get a new car. The value of the dollar goes down and we get less. Maybe you’re ok with that, but I personally like my quality of life.