ELIGIBILITY OF UNLEGITIMATED CHILDREN FOR DERIVATIVE
CITIZENSHIP
It is distinct from the acquisition of citizenship at birth, including the “citizenship by descent” that may be conferred on a child born abroad to a citizen parent.
See
id.; see also INA § 301(c), (d), (e), (g), 8 U.S.C. § 1401(c), (d), (e), (g) (2000) (examples of INA
provisions conferring citizenship by descent).
http://www.justice.gov/olc/2003/ins_opinion.pdf
Why do you keep responding with info on derivative citizenship? While that is certainly one way to become a U.S. citizen, the problem of becoming an "Accidental American" and therefore legally obliged to pay U.S. taxes regardless of where one lives in the world equally applies to children born in the U.S. to aliens just briefly in the country on vacation or just passing through. They literally have NO ties to the U.S. other than their mother giving birth in the U.S. during a brief stay in the country.