Canadian law is irrelevant to this discussion.
A citizen at birth is a natural born citizen and has never needed to be naturalized.
According to U.S.C Title 8 Section 1101 - Definitions (https://www.law.cornell.edu/uscode/text/8/1101) subsection A part (23), the term “naturalization” ONLY occurs after being born. Thus a person who, by the circumstances of their birth is a citizen, and never needs to be naturalized.
It is organic to a nation state to define it’s boundaries as well as it’s citizens. Every nation does this. The US Constitution vests the authority to determine the rules of naturalization - which includes all rules, with Congress. This is specifically enumerated in Article I Section 8.
Thus Congress is vested with the authority to determine who are aliens and need to be naturalized in order to be a citizen. It also is vested with the authority to determine who is a citizen. Some are citizens via naturalization, some are citizens AT BIRTH (the at birth is important). Congress has addressed this issue by determining who is a citizen at birth. The current state of the law is addressed in Title 8 section 1401 - Citizens at birth (https://www.law.cornell.edu/uscode/text/8/1401).
Under subsection A of that code, all who are born on US soil are US Citizens at birth and having never been naturalized are therefore natural born citizens
Under subsection G of that code (even the prior version), all who are born to at least one US citizen parent, as long as that parent has met the time requirements for residence inside the US, is also a citizen at birth. And like subsection A above, have never been naturalized and are therefore natural born citizens.
http://powderedwigsociety.com/eligibility-of-cruz-and-rubio/#
Pretty powerful and easy to understand presentation about Cruz and Rubio’s eligibility to run for POTUS.
A citizen at birth is a natural born citizen and has never needed to be naturalized.
You are so wrong. The very fact that application must be made to our consulate in a foreign country to receive a certificate requiring approval by said consul is not a natural act. A natural act is being born in an American hospital where a birth certificate is ROUTINELY issued and no proof is required other than the signature of the attending physician attesting to the actual birth. That is natural! Doing paperwork is not.
In any event, how is it possible to be a natural born citizen in TWO countries simultaneously? Cruz renounced his Canadian citizenship a few years ago.....so was it then that he became a natural born citizen? That last question was sarcasm. What a perfect world we would live in if only people engaged their brain before speaking. Golly, a natural born citizen of two countries!
Read the very first paragraph of this State Department directive: https://travel.state.gov/content/passports/en/abroad/events-and-records/birth.html