The question is this: what is the moral basis for denying people born in other countries the same work opportunities that people born in this country have? Why is it fair to call them "foreign" workers and say that american workers have more rights to jobs offered by american companies?
I've not understood this for a long time, and I'd honestly like to know what the argument for it is. It seems to me like the crux of the argument against sexism and racism and so on is that it's not fair to punish people for coincidences of their birth over which they had no control. Country of birth, just as much as sex and race, is nothing I chose. Why should a man be proud of being from the country he was born in when it's at least fairly often considered inappropriate to be proud of being a man, or proud of being white, or proud to have been born into a rich family?