從駐多倫多美大使館得到的權威答案-

再次謝謝8大哥的回複，但是，你看到的信息是不正確的。我也看到一些律師說不可同時持美加國籍。這的確是一個法律是不太明確的issue.

引號源來自大使館的回信：

"Dual nationality is allowed by the US government.

She will not lose her US citizenship by acquiring Canadian citizenship.

She must always enter the US as a US citizen"

同時，請大家看美駐多使館的官方website: http://toronto.usconsulate.gov/service/passports-and-citizenship.html),  “A U.S. citizen who naturalizes as a Canadian citizen may generally retain U.S. citizenship.”  “ Determination of dual nationality can only be made by applying for a U.S. passport or registration, not by phone or mail.”