Article I, Section 8, Clause 4:
[The Congress shall have Power . . .] To establish an uniform Rule of Naturalization, and uniform Laws on the subject of Bankruptcies throughout the United States; . . .
Naturalization has been defined by the Supreme Court as
the act of adopting a foreigner, and clothing him with the privileges of a native citizen. 1 In the Dred Scott case, 2 the Court asserted that the power of Congress under this clause applies only to
persons born in a foreign country, under a foreign Government. 3 These dicta are much too narrow to describe the power that Congress has actually exercised on the subject. The competence of Congress in this field merges, in fact, with its indefinite, inherent powers in the field of foreign relations.
As a government, the United States is invested with all the attributes of sovereignty. As it has the character of nationality it has the powers of nationality, especially those which concern its relations and intercourse with other countries. 4
Congress’s power over naturalization is an exclusive power; no state has the independent power to constitute a foreign subject a citizen of the United States. 5 But power to naturalize aliens under federal standards may be, and was early, devolved by Congress upon state courts of record. 6 And though the states may not prescribe requirements for citizenship, they may confer rights, including political rights, to resident aliens. At one time, it was not uncommon for states to confer the right of suffrage upon resident aliens, especially upon those who had declared their intention to become citizens, and several states continued to do so until well into the twentieth century. 7
Citizenship by naturalization is a privilege to be given or withheld as Congress may determine:
It is not within the province of the courts to make bargains with those who seek naturalization. They must accept the grant and take the oath in accordance with the terms fixed by the law, or forego the privilege of citizenship. There is no middle choice. 8 This interpretation makes of the naturalization power the only power granted in § 8 of Article I that is unrestrained by constitutional limitations on its exercise. Thus, the first naturalization act enacted by the first Congress restricted naturalization to
free white person[s], 9 which was expanded in 1870 so that persons of
African nativity and . . . descent were entitled to be naturalized. 10
Chinese laborers were specifically excluded from eligibility in 1882, 11 and the courts enforced these provisions without any indication that constitutional issues were thereby raised. 12 These exclusions are no longer law. Present naturalization statutes continue to require loyalty and good moral character and generally bar subversives, terrorists, and criminals, among others, from citizenship. 13
Although the usual form of naturalization is through individual application and official response on the basis of general congressional rules, naturalization is not so limited. Citizenship can be conferred by special act of Congress, 14 it can be conferred collectively either through congressional action, such as the naturalization of all residents of an annexed territory or of a territory made a state, 15 or through treaty provision. 16