No confusing on this end with regard to the Oath. Keep in mind our Supreme Court in the
Slaughterhouse Cases 83 U.S. 36, 73 (1873) wrote:
“[t]he phrase, ‘subject to its jurisdiction’ was intended to exclude from its operation children of … citizens or subjects of foreign States born within the United States .”
And how does a foreign national become subject to the jurisdiction of the United States under which birthright citizenship would be granted to a child born to a foreign national while on American soil? By first, and formally, taking our nation's Oath of Allegiance and becoming a citizen of the United States, and not owing
allegiance and fidelity to any foreign prince, potentate, state, or sovereignty.
And John A. Bingham, considered the architect of the 14th Amendment's first section was very clear on this requirement who stated on March 9th, 1866, during Congressional debates upon the intended meaning of “jurisdiction” in the following manner:
"I find no fault with the introductory clause [S 61 Bill], 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…" LINK (middle column 1/3 down)