The founding fathers wanted undivided loyalty hence the ‘natural born citizen’ requirement for the presidency - i.e. one born on US soil to 2 US citizen parents resulting in undivided loyalty to USA.
Even if one does not have to naturalize to be a US citizen, such as in Cruz’s case - he might have been a US citizen due to his mother’s US citizenship and he didn’t have to naturalize to be a US citizen, BUT he was born in foreign soil to a foreign father, so has dual citizenship/divided loyalty - he is a Canadian and a USA citizen!
If country of birth determines ‘nbc’ then Cruz is a nbc of Canada!
If the citizenship of 1 parent determines the child’s citizenship then Cruz is a Canadian due to his father, AND, a USA citizen due to his mother!
Can a person with dual citizenship and divided loyalty be the president of USA? Not according to The US Constitution !
I don’t think Canada has the same immigration laws as we do. For instance, someone born in Canada does not become automatically become Canadian. But, again, this would be better answered by a Canadian.
Anyhow, I more persuaded by the notion that both parents have to be American citizens at the time of birth and/or that the child was born in the USA or territories/area under its authority.
Cruz's father is Cuban, not Canadian. Cruz can claim citizenship from Canada, US, or Cuba. He's a threefer. (Like Obama.)