[DoctorBulldog]

I was taught the same thing in 7th grade in 1976 in Missouri. Obviously, there was a textbook somewhere that spelled it out, else how could teachers separated by decades and hundreds of miles teach that Natural Born meant born on American soil via two citizen parents? That’s proof enough for me that there exists a textbook somewhere that spells it out.

Cheers!

[Plummz]

Obviously, there was a textbook somewhere that spelled it out,

There is. It's called "The Law of Nations," and it's by Emer de Vattel.