U.S. Supreme Court said:
U.S. v. WONG KIM ARK, 169 U.S. 649 (1898)
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It thus clearly appears that by the law of England for the last three centuries, beginning before the settlement of this country, and continuing to the present day, aliens, while residing in the dominions possessed by the crown of England, were within the allegiance, the obedience, the faith or loyalty, the protection, the power, and the jurisdiction of the English sovereign; and therefore every child born in England of alien parents was a natural-born subject, unless the child of an ambassador or other diplomatic agent of a foreign state, or of an alien enemy in hostile occupation of the place where the child was born.
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That all children, born within the dominion of the United States, of foreign parents holding no diplomatic office, became citizens at the time of their birth, does not appear to have been contested or doubted until more than 50 years after the adoption of the constitution...
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There is, therefore, little ground for the theory that at the time of the adoption of the fourteenth amendment of the constitution of the United States there was any settled and definite rule of international law generally recognized by civilized nations, inconsistent with the ancient rule of citizenship by birth within the dominion. [169 U.S. 649, 668] Nor can it be doubted that it is the inherent right of every independent nation to determine for itself, and according to its own constitution and laws, what classes of persons shall be entitled to its citizenship.
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...it is beyond doubt that, before the enactment of the civil rights act of 1866 or the adoption of the constitutional [169 U.S. 649, 675] amendment, all white persons, at least, born within the sovereignty of the United States, whether children of citizens or of foreigners, excepting only children of ambassadors or public ministers of a foreign government, were native-born citizens of the United States.
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Mr. Justice Miller, indeed, while discussing the causes which led to the adoption of the fourteenth amendment, made this remark: 'The phrase 'subject to its jurisdiction' was intended to exclude from its operation children of ministers, consuls, and citizens or subjects of foreign states, born within the United States.'
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The fourteenth amendment, while it leaves the power, where it was before, in congress, to regulate naturalization, has conferred no authority upon congress to restrict the effect of birth, declared by the constitution to constitute a sufficient and complete right to citizenship.
No one doubts that the amendment, as soon as it was promulgated, applied to persons of African descent born in the United States, wherever the birthplace of their parents might have been; and yet, for two years afterwards, there was no statute authorizing persons of that race to be naturalized. If the omission or the refusal of congress to permit certain [169 U.S. 649, 704] classes of persons to be made citizens by naturalization could be allowed the effect of correspondingly restricting the classes of persons who should become citizens by birth, it would be in the power of congress, at any time, by striking negroes out of the naturalization laws, and limiting those laws, as they were formerly limited, to white persons only, to defeat the main purpose of the constitutional amendment.