One of the sharpest arguments in favor of immigration restriction was made, I believe, by Peter Brimelow in his book Alien Nation. My recollection is that it was more an aside in the introduction than a developed argument, (which if correct would be a shame), but the essence of it was the multiculturalism would inhibit and eventually render impossible a fully free society.I believe he's thinking of this passage:
We’ve seen plenty of evidence of Europe’s myriad difficulties reconciling multiculturalism and freedom of speech– from the vociferous reaction to publication of Salman Rushdie’s The Satanic Verses, to the Danish cartoon controversy, with many stops along along the way and more surely to come. I had assumed that America, with its vigorous First Amendment culture, would be much more resistant to the temptation to restrain speech.
"Immigrants do the dirty jobs no one else will touch." Americans are told, equally incessantly. I don't agree with this economic analysis either. But in this book, I act as if it were true. In discussing the many aspects of immigration policy, I inevitably touch on some issues of race and ethnicity that in American debate nowadays are usually taboo.Scott goes on to criticize the Daily News's Dolores Frida, [Send her mail] who, as Peter Brimelow noted below, doesn't believe in free speech for Marcus Epstein and VDARE.com, asking, finally "So, a question for Ms. Frida: what alterations in the US Constitution does she recommend as the “fair, safe, middle ground” to deal with such threats as Marcus Epstein?"
Taboos, however, are not just a matter of cowardice and mendacity. They also reflect a sincere human reluctance to give offense (which is why they tend to become rampant in diverse societies).[Emphasis added][Alien Nation, 1995, p. xvii (PDF)]