It’s an interesting question to say the least, but I’m not entirely sure. Say a kid was born 10 years ago, what has the federal government done to make his citizenship official? A Social Security number? Citizenship is not required to attend school. Welfare for his mother? I dunno. But it also raises the question of how this would be implemented. If a U.S. birth certificate is not evidence of citizenship, what would be? National ID?
Based on the lines I see at our post office, a lot of the anchor babies have passports.
No, we would use the same criteria that we use for births abroad. Jus sanguinis (by blood) will determine citizenship.
I think may have been given SS#s.