And they’re correct.
O’s mother was too young for her citizenship to have any effect on her first born, and according to The Law of Nations
§ 215. Children of citizens born in a foreign country
It is asked whether the children born of citizens in a foreign country are citizens? The laws have decided this question in several countries, and their regulations must be followed.(59) By the law of nature alone, children follow the condition of their fathers, and enter into all their rights (§ 212); the place of birth produces no change in this particular, and cannot, of itself, furnish any reason for taking from a child what nature has given him; I say “of itself,” for, civil or political laws may, for particular reasons, ordain otherwise. But I suppose that the father has not entirely quitted his country in order to settle elsewhere. If he has fixed his abode in a foreign country, he is become a member of another society, at least as a perpetual inhabitant; and his children will be members of it also.
O’s father was a VISITOR on a student visa, with no intention of making America his home, so O’s citizenship follows his fathers.
The definition of the term, “natural born citizen”, was entered into the Congressional record of the House on March 9, 1866, in comments made by Rep. John Bingham on the Civil Rights Act of 1866, which was the precursor to the Fourteenth Amendment. He repeated Vattel’s definition when he said:
“[I] find no fault with the introductory clause, which is simply declaratory of what is written in the Constitution, that every human being born within the jurisdiction of the United States of parents not owing allegiance to any foreign sovereignty is, in the language of your Constitution itself, a natural born citizen. . . . ” — John A. Bingham, (R-Ohio) US Congressman, March 9, 1866 Cong. Globe, 39th, 1st Sess., 1291 (1866), Sec. 1992 of U.S. Revised Statutes (1866).
Nor does the 14th Amendment make someone a citizen because they were born on American soil:
"Every Person born within the limits of the United States, and subject to their jurisdiction, is by virtue of natural law and national law a citizen of the United States. This will not, of course, include persons born in the United States who are foreigners, aliens, who belong to the families of ambassadors or foreign ministers accredited to the Government of the United States, but will include every other class of persons."
Senator Jacob Howard, co-author of the citizenship clause of the 14th Amendment, 1866.
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Not owing allegiance to any foreign sovereignty........Children of foreigners and aliens.....
That would seem do exclude children of African students here on a temporary visa, now wouldn't it?
Oh, and I don't know if you caught this thread, but it's an excellent resource on what "Subject to the Jurisdiction Thereof" Really Means.