美國憲法規定總統必須是natural born citizen。natural born citizen means citizen at birth. 並不是要求必須出生在美國國內。
出生在美國土地上的小孩,肯定是美國公民,都是citizen at birth.
出生在美國國外的美國公民的孩子,根據美國國籍法,出生就具有citizen,也是citizen at birth,也是natural born citizen.
A (born in US) is B (citizen at birth),C (born abroad to US parent(s)) is also B (citizen at birth).