Interesting discussions. The gray border case is that of a child born abroad to citizen parent(s). The case of child born in the US where one parent is a non-citizen is not a gray border case, it is in the area of settled cases. Such a child may become a citizen by law, but is NOT a natural born citizen.
Thus Obama is ineligible under the Law and there is no remedy for his case.
A Constitutional Amendment to change the requirements for Office would be the only remedy, and that is is an extremely unlikely event.
The editors eventually themselves settled on the more restrictive case that would exclude John McCain, or any other child of citizen Americans posted abroad in the service of their country. The editors decided that only those born in the US to citizen parents would be natural born citizens, although they noted other experts disputed that situation.
And for good reason as Britain still held a lot of territory in which the feudal law of jus soli & perpetual allegiance was still in effect thus making many foreign born children aliens of their parents. Imagine giving birth in a British state & having a child that must get permission from Parliament at the coming of age in order to renounce the perpetual hold that govt has on the person.
The US adopted the combination of jus soli & jus sanguinis as it is defined in Vattel, Pufendorf, Locke, Grotius, Montesquieu, Aristotle, De Tocqueville, etc, etc going all the way back to original Republican govt of Rome. It was the original law of England until shortly after the Norman conquest when feudal law was put in place that took the sovereignty from the people & place it with the king.
“The case of child born in the US where one parent is a non-citizen is not a gray border case, it is in the area of settled cases. Such a child may become a citizen by law, but is NOT a natural born citizen.”
You haven’t read the Constitution, have you?