Source, please. And, to be fair, a more appropriate measure would account for a nation’s population size and other factors reflecting its ability to absorb immigrants (e.g. space, economic health).
That is a point worth mentioning, but first it is important to acknowledge that there is nothing in the policies of the USA that can fairly be termed "isolationist" when something like 60 million residents in this country are foreign-born. The term is not only insulting but it's undeniably untrue.
Now, as to the bolded part of your post, I agree that "other factors" must be considered. Among them may be square mileage, as though immigration is nothing more than stacking bodies up in open space like shipping containers! Of course, that is a misleading way of thinking about numbers of immigrants, etc.
More relevant would be such considerations as how many refugees--from the whole world--can be accommodated in our schools, hospitals, industries, housing, and so on. It is not limitless, you should know, even if every one of them were skilled, law abiding, and everything else that's admirable.
We currently pay tens or hundreds of thousands of dollars annually for each immigrant in the form of welfare benefits, free care, and so on.
And each of those dollars comes out of what would otherwise be available to our own poor, the people who have, despite their own limited resources, paid taxes unlike the immigrants who have paid in exactly nothing upon entering the country.
By contrast, there is Canada. The Trudeau government made a point of announcing that Canada (unlike the USA presumably!) was welcoming towards immigrants! But not long thereafter, the authorities were alarmed and claiming to have been overwhelmed by a few
hundred immigrants arriving in Emerson, Manitoba. The Canadian publication,
Independent, reported this:
“We’ve had four cross this week – a Somali, a Honduran, someone from El Salvador, and even an American,” said Frank Suderman, manager of the Maple Leaf Motel, located a hundred yards from the border.
“It’s always at 2am or 5am. They knock on the door. You never know. We’ve always had people crossing, but never this many.”
