We are each and all born into a world with natural loyalties — at birth — to parents and to place. Those loyalties can be at odds. “Natural Born” means those circumstances of birth where the born allegiance is not at odds. For example a child of American’s on temporary travel abroad would have no natural allegiance to France, or Kenya — his or her allegiance would be to the permanent residence of his parents and where the child grows up.
That’s definitely the crux of the issue and maybe I just have to read deeper into Blackstone’s, because it’s that exclusivity of loyalty that I haven’t so much seen articulated.