Are you being dense on purpose? The US has been a country for 250 years and the Mayflower landed 400 years ago. Most of the people were born in the US.
Are you going to address that your statement does not square with the fact that the majority of the people in the 1870 census were not foreigners (born abroad) and therefore did not immigrate?
No. It doesn’t seem we can understand each other and I’d rather do other, more fulfilling things with my time. I don’t live in the US (thankfully) and don’t want to spend any more time arguing with you.