Clearly, the question of determining what is and what is not a “Natural-born” US citizen has never been adequately addressed. Is the US citizenship tied to the blood (one or both parents were citizens, either natural-born or naturalized, at time of birth of the applicant), or to the soil (the presence within US territory at time of birth, regardless of citizenship of the parents).
Apparently both are accepted under the current application of US law, and this has led to the anomalous situation where children born of non-citizens while residing in US territory, whether legally permitted to do so or not, have been granted a sort of provisional citizenship. There has been an attempt to extend this provisional citizenship to children born outside US territory, and brought into the US while in the custody of parents who themselves entered and are now residing here illegally.
______________
That is what seems to be happening.
Jus soli and Jus sanguine are necessary to be a natural born citizen.
If one is born with multiple citizenships, loyalties and allegiances, one is not naturally an American.