General Discussion
In reply to the discussion: Ted Cruz Citizenship Timeline: Ted Cruz is Canadian at birth. Period. [View all]Jim Lane
(11,175 posts)To take one famous example: Suppose there was a child born in Hawaii in 1961 to a US citizen mother and a UK citizen father from Kenya (which at that time was still a British colony, not an independent nation). Under US law, that child is a US citizen. But UK law also comes into play. IIRC the child would be a UK citizen but would lose that citizenship by not fulfilling UK residency requirements before the age of 21.
A perhaps clearer example: Two natural-born US citizens temporarily move to Canada, never do anything about Canadian citizenship, but while there they have a child. Shortly after the child's birth they move back to the US. Under the laws of the two nations, it's completely clear that the child is a US citizen at birth (because the US allows citizenship by ius sanguinis, the law of the blood) and a Canadian citizen at birth (because Canada allows citizenship by ius soli, the law of the soil).
Neither country's law can override the other's. Each country sets its own rules for determining citizenship. Nothing Canada does can deprive a person of US citizenship, even if the person was born in Canada.