Let's even say:
Everything gets made in USA.
The people in importing, customs, logistics would all be out of a job.
Prices would be higher, so exporting becomes difficult and sometimes impossible.
All foreign corporations close their US factories and produce and sell their stuff only in their countries. (You do want all countries to take care of themselves)
The jobless rates in retail, warehousing, transporation would be astronomical and the recession would be so bad, that it would last for years.
"Making" things in USA these days either involves automation with machines, so not many workers needed
or whatever is done by hand is usually done by latinos incl. illegals we can't do without.
(BTW: I keep predicting that (not in my lifetime) USA will eventually be a dual language country and Spanish will take over. These people make child after child and in some areas you are already lost if you don't speak Spanglish)
Ask yourself why USA lost and is losing so many production jobs? It's not just lower wages.
The politicians and business taxation and structures are totally business unfriendly.
USA has the habit to chase you into the grave to get a cut of every dollar you make, even when you no longer live in this country.
Since everything is money driven, businesses make sure they only pay the minimum necessary for ANYTHING.
I do not go to any store and say, here is an extra dollar, I am glad it's made in USA. Pipe dream.
Trying to isolate USA from the world isn't going to work.
So, if you want to be objective, acknowledge that business is global.
If you can't do that ................