Money if fungible. California spends an enormous amount of money on illegal aliens (illegal immigrants). For example, there was an NYT op-ed piece which explained that 200 illegal aliens are allowed to attend at in-state tuition UC Berkeley. Thus, the Federal Funds noted in this article were in fact being used to fund people who are residing in this country illegally. We don't even have enough money for the poor who…
https://en.wikipedia.org/wiki/Bracero_program
This set expectations for generations of businesses and workers and obviously continues to this day. The re-branding of welcome migrant workers to vile illegal aliens is just politics.
Do migrants depress the wages of American workers? Probably to some degree (I suppose it's like the H1B visa program). Do they interfere with the sovereignty of the United States? I think the argument is ridiculous, just pandering to nationalists.