U.S. citizen at birth means a “natural born citizen” i.e. not a “naturalized” citizen.
I never claimed there was no distinction between a “natural born citizen” and a “U.S. citizen”, please engage what I actually said rather than what you thought I said.
My Governor is a U.S. citizen, but he is a naturalized immigrant and not a natural born citizen. In other words (for those of you in Rio Linda) he was not a U.S. citizen AT BIRTH.
That the language differentiates between "natural born citizen" and "citizen" in that language means that there is a difference between the two, with "citizen" not being naturalized.
So, "natural born citizen" means something more than a U. S. citizen at birth.
Shall we make you an honorary citizen of Rio Linda?