8 U.S. Code § 1449 - Certificate of naturalization; contents

A person admitted to citizenship in conformity with the provisions of this subchapter shall be entitled upon such admission to receive from the Attorney General a certificate of naturalization, which shall contain substantially the following information: Number of application for naturalization; number of certificate of naturalization; date of naturalization; name, signature, place of residence, autographed photograph, and personal description of the naturalized person, including age, sex, marital status, and country of former nationality; location of the district office of the Service in which the application was filed and the title, authority, and location of the official or court administering the oath of allegiance; statement that the Attorney General, having found that the applicant had complied in all respects with all of the applicable provisions of the naturalization laws of the United States, and was entitled to be admitted a citizen of the United States of America, thereupon ordered that the applicant be admitted as a citizen of the United States of America; attestation of an immigration officer; and the seal of the Department of Justice.

Question- If this person who was just naturalized has a certificate stating they are a citizen of the United States of America, are they also subject to laws that fail to state United States of America in their definitions?

Question- If "United States" = "United States of America", why does 8 USC 1449 refer to both?

Question- Why does the Internal Revenue Code define "United States", but fails to define "United States of America" and fails to list the names of the 50 states in the definitions of "state"?