Settled law, as per constitutional authority.
When? How? Who is the "constitutional authority?
It's never been ruled on one way or another, and Congress cannot change the Constitution by legislative act, only by amendment with consent of the states. Saying it's "settled law" is just nonsense.
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A congress of mostly founders passed a resolution that the child of a citizen is also a citizen, without regard of place of birth.
Logically they knew what the constitution they had created intended.
It has actually never been in question.
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