A good article on the subject:
I get tired of arguing the NBC issue because even the conservatives that are close to my position (like at WND) undermine the basic logic of NBC by insisting that US citizenship is required of both parents–which of course is ludicrous because that leads in some cases to individuals not being NBC of ANY country. (Natural law demands that every individual must be a NBC of one and ONLY one country.) As uncomfortable as it is to the modern mind, the rule must be father’s citizenship. Must be one or the other, and by tradition it’s the father. Still makes more sense because fathers typically have a greater role in politics outside the home, and in dying on the battlefield.