It isn't a question of whether or not the US needs immigration. It's a question of doing it in an orderly and productive way.
Any characterization to the contrary is false, notwithstanding the furthest fringes of the political spectrum who think immigration should be zero.
Of course we want immigrants- but we need to know who they are, and we need to try to pace it so that we don't end up with enclaves that fail to integrate with the broader society. That latter part has always been a problem, in every immigration wave the US has been through.
We are not doing that right now, and it's for political reasons. That's counterproductive, no matter which side of the argument a person happens to be.
If we addressed it in an intelligent way, it would remove it as a political wedge issue, and neither party really wants that- so it becomes part of the culture war and there it will stay.