Where, Canada?
Oh wait, he renounced his Canadian citizenship.
No, the United States of America. There is no "dual loyalty" issue here.
Most experts believe Cruz is a natural born citizen, but no president has ever been born outside the U.S.
And "most experts" would also include a unanimous US Supreme Court, which includes Justices like Clarence Thomas.
Now, if anyone would like to make the argument that Clarence Thomas isn't a conservative Justice—or that he'd be inclined to rule Ted Cruz ineligible—please, proceed.
Personally, believe that if Clarence Thomas and his ilk would consider Ted Cruz eligible, then there's not much point in forwarding gratuitous and whimsical eligibility arguments which apparently don't have a legal leg to stand on—even with stalwart "strict constructionists".
Knowing Ted Cruz, I'm confident that this question will eventually be ruled on by a conservative USSC—and in his favor...