He was not naturalized - he was born a natural citizen.
Sanguine, I believe that you are using a very limited definition of "naturalization." We commonly see it as the process in which individuals voluntarily go through a proactive process to become a US citizen, culminating with the person being naturalized taking an oath of allegiance to the US.
In a more general (and legal) sense,
naturalization is the process under federal law whereby a foreign-born person may be granted citizenship. Collective naturalization, the most common form of naturalization, occurs when groups of foreign-born people are granted citizenship via legislation enacted by Congress (also referred to as citizenship by statute).
It was what I was referring to in the post above on which you commented. There is no dispute that Mr. Cruz's US citizenship (conferred at his birth, assuming all of the relevant birth facts in common acceptance are accurate), is the result of collective naturalization, made possible by legislatively constructed statute.
There is a very instructive Supreme Court case,
Rogers v. Bellei 401 U.S. 815 (1971), while not focused on the specifics of Ted Cruz's citizenship origins, contains a very good discussion on the specifics of citizenship via statute. If I get a chance sometime, I would like to spend the time to highlight the findings of this case that bear on the current discussion. Here is one particular quote of note:
"Any child hereafter born out of the limits and jurisdiction of the United States, whose father or mother or both at the time of the birth of such child is a citizen of the United States, is declared to be a citizen of the United States; but the rights of citizenship shall not descend to any such child unless the citizen father or citizen mother, as the case may be, has resided in the United States previous to the birth of such child. In cases where one of the parents is an alien, the right of citizenship shall not descend unless the child comes to the United States and resides therein for at least five years continuously immediately previous to his eighteenth birthday, and unless, within six months after the child's twenty-first birthday, he or she shall take an oath of allegiance to the United States of America as prescribed by the Bureau of Naturalization."
I assume that Mr. Cruz and his parents have meet all of the obligations described above, hence that is why his US
citizenship is not in question. But in reviewing the above, and the rest of
Rogers v. Bellei, you can see the clear distinctions (and inherent legislatively imposed constraints) that have been drawn (in other SC cases as well) between citizenship by statute, and natural born citizenship.
I will use myself as an example. I was born in the United States to two citizen parents. My citizenship is granted (
by nature) owing to the place of my birth (jus soli), and the undivided loyalties of my citizen parents (jus sanguinis), under the sole governance of the United States Constitution. That is, my citizenship does
not depend on the existence of any statutory actions taken by the US Congress (nor can it ever be constrained by such); hence I am a
natural born citizen.