Debating they why of this gets into the stuff of politics, but the what is that the infrastructure for the production of labor-intensive / lower-end consumer goods has receded from the US economy. The prior workforce has largely retired or moved on, the value proposition for prospective future candidates is not palatable, the suppliers are no longer present, and the labor advantage in other countries is too persuasive to ignore. What's manufactured here tends to be upper-end goods that are capital- or intellectual property-intensive to produce because that's where the US's advantage lies.I mean, all else equal, they (nor anyone else) don't have a fundamental principle to buy from overseas.
If you think that any US business wants to deal with language barriers, time zone barriers, exchange rate issues, having the delay to ship via water/containers, etc when they don't have to, then you are fooling yourself.
Not many people want to work in a factory anymore... especially making cheap consumer items.