“This is settled law”
What statute or court case are they basing this as settled law?
Here’s the Statute: Title 8’ Section 1401 of the U.S. Code of Laws:
The following shall be nationals and citizens of the United States at birth:
(g) a person born outside the geographical limits of the United States and its outlying possessions of parents one of whom is an alien, and the other a citizen of the United States who, prior to the birth of such person, was physically present in the United States or its outlying possessions for a period or periods totaling not less than five years, at least two of which were after attaining the age of fourteen years...
http://www.law.cornell.edu/uscode/text/8/1401