That relies on the premise that immigration of "ordinary" people is somehow detrimental to the existing US population. This is, to my knowledge, not supported by any fact or study.
Low skilled immigrants compete against low skilled workers that are already here and depress their wages. High skilled workers do the same thing but at the top end with the added advantage of generating more tax dollars and GDP (since they have more income).
At its core the question becomes: Is immigration a public policy to benefit those that are here (ie strengthen economy, unify familial bonds) or a charity offered to the rest of the world?
Edit: To be fair - I can see the argument for a supply of immigrant low skill workers potentially keeping wages depressed hitting existing US residents and while it might be good for the wealthy and businesses it might not be good for the majority. I'm in the UK and these arguments are very similar to those covered in the Brexit campaigns and while I voted Remain and I've since come to appreciate more of the arguments on the other side.
Young unskilled workers are a net gain to the economy, especially in an ageing society like the US. It's not charity.
How so?