Hoover Institution economist Thomas Sowell nearly always gets to the heart of the matter. This includes, over the years, immigration. (See, for example, this 1997 essay from Forbes, reprinted in The Social Contract.)
Apparently, there's nothing about immigration in the book, but Steigerwald and Sowell get onto our subject, anyway. I'll just point you to highlight quotes from Sowell:
I’m amazed when they talk about the guest-worker program in Europe. No one even asks, ”What has happened with guest-worker programs in Europe?” What has happened is that they’ve brought in people who hate their guts. This is why you have terrorism in London and Madrid and riots in Paris and other French cities by people who have absolutely no desire to assimilate and who in fact hate the very ideas of the country in which they live.
There is the second-generation phenomenon. You have people who move in from some poor country — the Middle East, Mexico, whatever. Those people may be very glad to be in the United States or Britain or wherever they may be. But then they have children. And their children have never seen those other places; they’ve never lived that poorer life. All they know is that the population around them is a hell of a lot more prosperous than they are. And there are all sorts of ideologues and hustlers ready to tell them that it’s society’s fault that they don’t have what other people have. This then gives you the people who hate the country in which they live.
[People] love to say things like, ”They thought the Irish and the Jews were unassimilable but look at them now, etc.” Well, the circumstances of the Irish and the Jews were radically different from the circumstances of the people who are coming here from Central America.
First of all, the times were different. First of all, the Irish, the Jews and blacks as well, who were moving out of the South, had leaders and organizations that were doing their damnedest to get them assimilated to the norms and the society to which they were moving.
Today, you have just the direct opposite. You not only have groups within in these societies that are trying to keep them unassimilable and full of resentment. But you also have people from outside the group, including politicians but also ideologues and intellectuals, who say one culture is as good as another and why should we expect them to assimilate to our culture. Well, that’s wonderful. You should try to go to China and live without speaking Chinese.
Would you like a bit more from Sowell? Then please read his brief essay "Multicultural Education," written in the early 1990s. The essay contains nothing specifically about immigration. But it is probably the most potent and condensed defense of Western civilization you will ever encounter.