The reason so many Americans are out of work is because their (prior) jobs were “outsourced” to countries with much cheaper labor.

Outsourcing and immigration are separate issues.

I personally have a problem with Chinese factories who have made money hand over fist manufacturing “engineered” or “laminate hardwood floors” for YEARS for giant US retailer Lumber Liquidators using (toxic) formaldehyde in the process. That’s disgusting and never would have happened had the flooring been manufactured inside the borders of the US.

US firms have never done harm?

Ever heard of the Michigan PBB incident?
How about the Macondo oil spill?
Or formaldehyde in good ‘ol US-made plywood in the 80s?