with whom Mr. Justice Stewart joins as to Part II, dissenting.
The Court holds that one may lose United States citizenship if the Government can proves by a preponderance of the evidence that certain acts, specified by statute, were done with the specific intent of giving ups citizenship. Accordingly, the Court, in reversing the judgment of the Court of Appeals, holds that the District Court applied the correct evidentiary standards in determining that appellee was properly stripped of his citizenship. Because I would hold that one who acquires United States citizenship by virtue of being born in the United States, U. S. Const., Arndt. 14, § 1, can lose that citizenship only by formally renouncing it, and because I would hold that the act of which appellee is accused in this case cannot be an expatriating act, I dissent.
I
This case is governed by Afroyim v. Rusk, 387 U. S. 253 *275(1967). Afroyim, emphasizing the crucial importance of the right of citizenship, held unequivocally that a citizen has “a constitutional right to remain a citizen . . . unless he voluntarily relinquishes that citizenship.” Id., at 268. “[T]he only way the citizenship . . . could be lost was by the voluntary renunciation or abandonment by the citizen himself.” Id., at 266. The Court held that because Congress could not “abridge,” “affect,” “restrict the effect of,” or “take . . . away” citizenship, Congress was “without power to rob a citizen of his citizenship” because he voted in a foreign election. Id., at 267.
The same clearly must be true of the Government’s attempt to strip appellee of citizenship because he swore an oath of allegiance to Mexico.1 Congress has provided for a procedure by which one may formally renounce citizenship.2 In this case the appellant concedes that appellee has not renounced his citizenship under that procedure.3 Brief for Appellant 56. Because one can lose citizenship only by voluntarily renouncing it and because appellee has not formally renounced his, I would hold that he remains a citizen. Accordingly, I would remand the case with orders that ap-pellee be given a declaration of United States nationality.4
*276II
I reach the same result by another, independent line of reasoning. Appellee was bom a dual national. He is a citizen of the United States because he was bom here and a citizen of Mexico because his father was Mexican. The only expatriating act of which appellee stands accused is having sworn an oath of allegiance to Mexico. If dual citizenship, per se, can be consistent with United States citizenship, Perkins v. Elg 307 U. S. 325, 329 (1939),5 then I cannot see why an oath of allegiance to the other country of which one is already a citizen should create inconsistency. One owes allegiance to any country of which one is a citizen, especially when one is living in that country. Kawakita v. United States, 343 U. S. 717, 733-735 (1952).6 The formal oath adds nothing to the existing foreign citizenship and, therefore, cannot affect his United States citizenship.
He was a Mexican citizen by virtue of bis father’s citizenship.
Title 8 U. S. C. § 1481 (a) (6) provides that “a national of the United States whether by birth or naturalization, shall lose his nationality by . . . making a formal renunciation of nationality before a diplomatic or consular officer of the United States in a foreign state, in such form as may be prescribed by the Secretary of State.” The Secretary of State has prescribed such procedures in 22 CFR §50.50 (1979). See Department of State, 8 Foreign Affairs Manual §225.6 (1972). Congress also provided for renunciation by citizens while in the United States in 8 U. S. C. § 1481 (a) (7). This last provision is not relevant to our case.
Therefore, the appellant does not argue that appellee can be expatriated under 8 U. S. C. § 1481 (a) (6). See n. 2, supra.
I would not reach the issues concerning 8 U. S. C. § 1481 (c).
Rogers v. Bellei, 401 U. S. 815 (1971), is not to the contrary. Bellei’s citizenship was not based on the Fourteenth Amendment, id., at 833, 835, and the issue before the Court was whether Bellei could lose his statutory citizenship for failure to satisfy a condition subsequent contained in the same statute that accorded him citizenship.
Indeed, the opinion of the State Department once was “that a person with a dual citizenship who lives abroad in the other country claiming him as a national owes an allegiance to it which is paramount to the allegiance he owes the United States.” Kawakita v. United States, 343 U. S., at 734-735.