Immigrants are vital, but also, there's such a thing as too much of an influx at once. Which incidentally isn't the fault of the immigrants, but is usually the fault of the monetary system, or other policy (like the damming of the rivers that turned Mexican farmland fallow a century ago).
We should seek to conduct ourselves as a nation in such a way that doesn't force people to flood into our country out of desperation, leaving their families and homes behind, and then need to contend with the influx itself. We're paying on both ends, and blaming the people we victimize twice while those whose stock options and election prospects are on the rise are the actual culprits of the imbalances.
The other ones victimized twice, incidentally, are the working class Americans often losing their jobs to the policies that go abroad and ultimately drive the immigration, who get to watch their kids unable to get jobs too.
Keeping us at each other's throats is how those behind these trends maintan power.
And damn lol if I keep this up I'll sound likes a socialist, except that I recognize these acts of foreign aggression as those carried out by unjust totalitarian power brokers. Capitalism isn't the problem, it is the solution. Externalization of costs isn't capitalism, it's theft of private property rights, and reappropriation of resources.