The founders, signers of the Declaration and drafters of the Constitution, were all born British subjects of the King. It was because of that that THEY were not ‘natural born citizens,’ and exempted themselves, reasonably enough, from that qualifier for president.”
Actually, it's much simpler than that. You simply can't be a natural born citizen of a country that didn't exist when you were born. That's the obvious fact they were addressing. It doesn't represent a definitive determination about what they thought of people born in the US with a non-citizen parent.
“It doesn’t represent a definitive determination about what they thought of people born in the US with a non-citizen parent.”
Not a definitive determination? There is ample documentation that the Framers were adamant, and adopted specific language to assure, that he who would be president and commander in chief be of singular loyalty to the new nation for which they had sacrificed their lives, their fortunes and sacred honor.
The Founders were all well versed, educated men of their time, and all familiar with Vattel’s “Law of Nations.” In the nomenclature of the time, ‘natural born’ meant the child of citizen parents, as was understood by each and every drafter and signer of the Constitution. Had they wanted the president/Commander in Chief to be merely a citizen, they’d have established the eligibility requirements as they did for members of the Senate and House of Representatives.