I do believe Boris renounced his US citizenship a few years ago, but I think it’s Prince Harry’s wife who really has her eyes on that office.
If he did renounce it, it would have been done because of British law. But say he didn’t have to. Let’s, for the sake of the arguement, say he became a Canadian Prime Minister. Under Canada’s law, you can be a dual-citizen and run for Prime Minister, as long as one of those citizenships is Canadian.
Could somebody born in the US, who remains a US citizen but becomes a dual citizen and becomes Prime Minister of Canada run as President if he then gives up his dual citizenship and becomes fully American?
I understand that shouldn’t happen, as intended by the Founding Fathers, but it’s the reality today.