> All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside.
The question presented by the record is whether a child born in the United States, of parents of Chinese descent, who, at the time of his birth, are subjects of the Emperor of China, but have a permanent domicil and residence in the United States, and are there carrying on business, and are not employed in any diplomatic or official capacity under the Emperor of China, becomes at the time of his birth a citizen of the United States, by virtue of the first clause of the Fourteenth Amendment of the Constitution, “All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside.”
(https://www.govinfo.gov/content/pkg/USREPORTS-169/pdf/USREPO...)And I quote:
The interpretation of the Constitution of the United States is necessarily influenced by the fact that its provisions are framed in the language of the English common law, and are to be read in the light of its history.
and further: The fundamental principle of the common law with regard to English nationality was birth within the allegiance, also called “ligealty,” “obedience,” “faith” or “power,” of the King. The principle embraced all persons born within the King’s allegiance and subject to his protection. Such allegiance and protection were mutual — as expressed in the maxim, protectio trahit subjectionem, et subjectio protectionem — and were not restricted to natural-born subjects and naturalized subjects, or to those who had taken an oath of allegiance ; but were predicable of aliens in amity, so long as they were within the kingdom. Children, born in England, of such aliens, were therefore natural-born subjects. But the children, born within the realm, of foreign ambassadors, or the children of alien enemies, born during and within their hostile occupation of part of the King’s dominions, were not natural-born subjects, because not born within the allegiance, the obedience, or the power, or, as would be said at this day, within the jurisdiction of the King.
among other things, upon which it was concluded that The foregoing considerations and authorities irresistibly lead us to these conclusions: The Fourteenth Amendment affirms the ancient and fundamental rule of citizenship by birth within the territory, in the allegiance and under the protection of the country, including all children here born of resident aliens, with the exceptions or qualifications (as old as the rule itself) of children of foreign sovereigns or their ministers, or born on foreign public ships, or of enemies within and during a hostile occupation of part of our territory, and with the single additional exception of children of members of the Indian tribes owing direct allegiance to their several tribes. The Amendment, in clear words and in manifest intent, includes the children born, within the territory of the United States, of all other persons, of whatever race or color, domiciled within the United States. Every citizen or subject of another country, while domiciled here, is within the allegiance and the protection, and consequently subject to the jurisdiction, of the United States. His allegiance to the United States is direct and immediate, and, although but local and temporary, continuing only so long as he remains within our territory, is yet, in the words of Lord Coke, in Calvin's Case, 7 Rep. Qa, “ strong enough to make a natural subject, for if he hath issue here, that issue is a natural-born subject; ” and his child, as said by Mr. Binney in his essay before quoted, “if born in the country, is as much a citizen as the naturalborn child of a citizen, and by operation of the same principle.”
and To hold that the Fourteenth Amendment of the Constitution excludes from citizenship the children, born in the United States, of citizens or subjects of other countries, would be to deny citizenship to thousands of persons of English, Scotch, Irish, German or other European parentage, who have always been considered and treated as citizens of the United States.
Regardless of whether birthright citizenship is appropriate contemporary policy, changing it would require an Amendment to the Constitution.