Now you have clarified the problem. It isn't our changing demographics. It is the Mexicans that you see as one of the three big problems ... actually the biggest because you have lost the other two in your zeal for this one.
I like Mexicans, although I do admit I don't live in or near a big-city urban area. But the rural Mexicans I know are genuinely happy, hard working, family-oriented and moral. I don't see the problem.