>Well, the United States is a living example of a country that tried that, and um ... hasn't failed because of it. When did the US A) allow unrestricted immigr

>Well, the United States is a living example of a country that tried that, and um ... hasn't failed because of it. When did the US A) allow unrestricted immigration of people of non-European origin, B) actually have significant numbers of immigrants of non-European origin, and C) not quickly move to restrict that immigration? Unrestricted immigration of people of European origins is not the same thing as opening up the borders without restriction.