TITLE 8 >
CHAPTER 12 >
SUBCHAPTER I > § 1101
§ 1101. Definitions
(3) The term “alien” means any person not a citizen or national of the United States.
(21) The term “national” means a person owing permanent allegiance to a state.
(22) The term “national of the United States” means (A) a citizen of the United States, or
(B) a person who, though not a citizen of the United States, owes permanent allegiance to the United States.
(30) The term “passport” means any travel document issued by competent authority showing the bearer’s origin, identity, and nationality if any, which is valid for the admission of the bearer into a foreign country.
(38) The term “United States”, except as otherwise specifically herein provided, when used in a geographical sense, means the continental United States, Alaska, Hawaii, Puerto Rico, Guam, and the Virgin Islands of the United States.
[Hmmm, here it doesn't refer to the U.S. as D.C. and it's territiories.]
In USC title 18, there is no reference to "American" as pertaining to this subject.
So then one would say they are a, for example, a California National.