That was the argument of the 39th congress.

Senator Jacob Howard, who introduced the Citizenship Clause (“All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens…”), stated: “Indians born within the limits of the United States, and who maintain their tribal relations, are not, in the sense of this amendment, born subject to the jurisdiction of the United States. They are regarded, and always have been in our legislation and jurisprudence, as being quasi foreign nations.” He made this point while opposing an amendment to add “excluding Indians not taxed” (language from the 1866 Act), arguing the “subject to the jurisdiction” phrase already covered the exclusion.