Aside from the short list of so-called awakened neo-cons you provided (and to my knowledge Daniel Pipes has always been concerned about immigration), truth is very few neo-cons have changed their tune about immigration since 9/11. And I shutter to think what it would take to wake up most of these pseudo conservatives to the immigration crisis in America.
The real problem is thta most neocons are white ethnics. They believe in the immigation myths of the early 20th century. Their attachment is not to the America of 1789, but to 1910. Their ideal of America is not found in Democracy in America or the Federalist Papers but in the Hollywood "American dream."
White ethnic intellectuals have defined their group identity in opposition to the WASPS. They associate assimilating to 1800 to become a WASP. Thus they created a new America. In effect, they believe in a "melting pot" where immigrants keep their identity but switch allegience to America, but it is America which must change. To accept that ideas are based on a culture and that America has a national identity would force them to confront their cultural identities.
How many of them can truly agree with the following though by Teddy Roosevelt?
"There is no room in this country for hyphenated Americanism.... A hyphenated American is not an American at all... Americanism is a matter of the spirit, and of the soul...The one absolutely certain way of bringing this nation to ruin, of preventing all possibility of its continuing to be a nation at all, would be to permit it to become a tangle of squabbling nationalities, an intricate knot of German-Americans, Irish-Americans, English-Americans, French-Americans...each preserving its separate nationality.... The men who do not become Americans and nothing else are hyphenated Americans.... There is no such thing as a hyphenated American who is a good American."They refuse to accept that you can be an American and a Jew or Irishman, but you need to be an American first and foremost.