I think the economics here are not that reductive. Yes, American domestic workers were displaced. And, lots of other Americans made a lot of money in their Roth, and got to buy cheaper goods and services. Doesn't help the unemployment problem. Did help everyone else.
The same pressures are visible in Germany. Merkel responded to business need for 1.5m more workers. The overwhelming majority are productive and enough are visibly not, and different she's ignited a racist backlash. Nobody has managed to convince me the 1.5m body count wasn't needed.
America has always grown economically through immigration. It's also always been painful.
As you mentioned earlier though, the issue isn't immigration per se, but the scale of it, which has been accelerating even though its been obvious for some time that we're already beyond the point at which it is beneficial to economy or society in other ways. The backlash is inevitable - it doesn't benefit the lives or ordinary folk. It must be scaled back, but if governments aren't willing to remedy that, they'll invite in a populist government which will turn the needle the other way, as has happened in the US.
Turning the needle the other way will also likely to be detrimental to the economy in the long term, but the insistence on labelling ordinary people with legitimate concerns as "racist" so as to ignore them is what has created the political division, absence of any centrist politics, and rise of extremism on both sides.
The remedy is to scale back the rate of immigration, not cut it out entirely.
The same pressures are visible in Germany. Merkel responded to business need for 1.5m more workers. The overwhelming majority are productive and enough are visibly not, and different she's ignited a racist backlash. Nobody has managed to convince me the 1.5m body count wasn't needed.
America has always grown economically through immigration. It's also always been painful.