Natural born Citizen is NOT the same as natural born subject. The founders very specifically rejected the idea of natural born subjects, a term implying an irrevocable fealty to an elite sovereign. Natural born subject was a term of ownership and was used, among other things, to justify impressing as many able bodied, but otherwise unwilling "subjects" into his majesty's royal service as possible (typically as sailors). For this reason (gathering up as many able bodies as possible), qualification as a natural born subject was like a logical OR operation, thus being born of either of the blood of a subject or within the king's realm was qualification enough.
The founders thoroughly rejected this idea and considered every citizen as sovereign -- we were founded as a nation of sovereign Citizens, none higher than any other. Politicians, even up to and including the president, were intended to be the servants of We the People, the exact opposite of the system natural born subjects suffer under. The founders were familiar with the term and concept of "natural born subject" and they rejected it in its entirety.
Furthermore, it is ludicrous on its face to assume that the founders, who were articulately deliberate and elegantly succinct in their writings, inserted an entirely superfluous word into the phrase "natural born Citizen." If they had meant only "born citizen" that is exactly what they would have written, but they did not. As Chief Justice Roger B. Taney wrote in Holmes v. Jennison (1840):
"In expounding the Constitution of the United States, every word must have its due force, and appropriate meaning; for it is evident from the whole instrument, that no word was unnecessarily used, or needlessly added. The many discussions which have taken place upon the construction of the constitution, have proved the correctness of this proposition; and shown the high talent, the caution, and the foresight of the illustrious men who framed it. Every word appears to have been weighed with the utmost deliberation, and its force and effect to have been fully understood."The purpose of the presidential eligibility requirement was to ensure that those born with a naturally divided allegiance be excluded from ever becoming our commander-in-chief. For this reason, qualification as a natural born Citizen was like a logical AND operation, thus one must born one hundred percent exclusively American, both of blood (of two citizen parents) and of dirt (within our territorial jurisdiction).
It may not make sense to you but it appears to make sense to judges and members of Congress.
It was Supreme Court Justice Horace Gray, writing for the majority in U.S. v Wong Kim Ark in 1898 who made the definitive statement of connection between natural born subject and natural born citizen. I know of no judge and no member of Congress who has challenged that statement of connection over the last 117 years.
Mr. Justice Gray wrote: “[An alien parent’s] 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 Coke, 6a, ’strong enough to make a natural subject, for, if he hath issue here, that issue is a natural-born subject’
“Subject’ and ‘citizen’ are, in a degree, convertible terms as applied to natives; and though the term ‘citizen’ seems to be appropriate to republican freemen, yet we are, equally with the inhabitants of all other countries, ’subjects,’ for we are equally bound by allegiance and subjection to the government and law of the land.’
…every child born in England of alien parents was a natural-born subject, unless the child of an ambassador or other diplomatic agent of a foreign state, or of an alien enemy in hostile occupation of the place where the child was born.
The same rule was in force in all the English colonies upon this continent down to the time of the Declaration of Independence, and in the United States afterwards, and continued to prevail under the constitution as originally established.”
Coincidently, Founder and Framer and “Father of the Constitution” James Madison accepted French Citizenship and thus became a dual citizen.
I don’t think that there are many people who would question James Madison’s allegiance.