The Unconstitutionality of Slavery (Complete Edition). Lysander Spooner

The very improper power would still be retained by each State, of naturalizing aliens in every other State. In one State, residence for a short time confers all the rights of citizenship; in another, qualifications of greater importance are required. An alien, therefore, legally incapacitated for certain rights in the latter, may, by previous residence only in the former, elude his incapacity, and thus the law of one State be preposterously rendered paramount to the laws of another, within the jurisdiction of the other.

      “We owe it to mere casualty, that very serious embarrassments on this subject have been hitherto escaped. By the laws of several States, certain descriptions of aliens, who had rendered themselves obnoxious, were laid under interdicts inconsistent, not only with the rights of citizenship, but with the privileges of residence. What would have been the consequence, if such persons, by residence, or otherwise, had acquired the character of citizens under the laws of another State, and then asserted their rights as such, both to residence and citizenship, within the State proscribing them? Whatever the legal consequences might have been, other consequences would probably have resulted of too serious a nature, not to be provided against. The new constitution has, accordingly, with great propriety, made provision against them, and all others proceeding from the defect of the confederation on this head, by authorizing the general government to establish an uniform rule of naturalization throughout the United States.”

      Throughout this whole quotation Mr. Madison obviously takes it for granted that the word “free” is used in the articles of confederation, as the correlative of aliens. And in this respect he no doubt correctly represents the meaning then given to the word by the people of the United States. And in the closing sentence of the quotation, he virtually asserts that such is the meaning of the word “free” in “the new constitution.”