"And the Constitution itself is in every real sense a law-the lawmakers being the people themselves, in whom under our system all political power and sovereignty primarily resides, and through whom such power and sovereignty primarily speaks. It is by that law, and not otherwise, that the legislative, executive, and judicial agencies which it created exercise such political authority as they have been permitted to possess. The Constitution speaks for itself in terms so plain that to misunderstand their import is not rationally possible. 'We the People of the United States,' it says, 'do ordain and establish this Constitution.' Ordain and establish! These are definite words of enactment, and without more would stamp what follows with the dignity and character of law. The framers of the Constitution, however, were not content to let the matter rest here, but provided explicitly-'This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; ... shall be the supreme Law of the Land.' (Const. art. 6, cl. 2.) The supremacy of the Constitution as law is thus declared without qualification. That supremacy is absolute; the supremacy of a statute enacted by Congress is not absolute but conditioned upon its being made in pursuance of the Constitution. And a judicial tribunal, clothed by that instrument with complete judicial power, and, therefore, by the very nature of the power, required to ascertain and apply the law to the facts in every case or proceeding properly brought for adjudication, must apply the supreme law and reject the inferior statute whenever the two conflict. In the discharge of that duty, the opinion of the lawmakers that a statute passed by them is valid must be given great weight, Adkins v. Children's Hospital, 261 U.S. 525, 544, 43 S.Ct. 394, 24 A.L.R. 1238; but their opinion, or the court's opinion, that the statute will prove greatly or generally beneficial is wholly irrelevant to the inquiry. Scechter Poultry Corp., v. United States, 295 U.S. 495, 549, 550 S., 55 S.Ct. 837, 97 A.L.R. 947.

..."we reaffirmed our consistent rule:

"Congressional power over areas of private endeavor, even when its exercise may pre-empt express state-law determinations contrary to the result that has commended itself to the collective wisdom of Congress, has been held to be limited only by the requirement that `the means chosen by [Congress] must be reasonably adapted to the end permitted by the Constitution.' Heart of Atlanta Motel, Inc. v. United States, 379 U.S. 241, 262 (1964)." Id., at 840.

"The Court noted, however, that 'the States as States stand on a quite different footing from an individual or corporation when challenging the exercise of Congress' power to regulate commerce.' Id., at 854. It indicated that when Congress attempts to directly regulate the States as States the Tenth [452 U.S. 264, 287] Amendment requires recognition that 'there are attributes of sovereignty attaching to every state government which may not be impaired by Congress, not because Congress may lack an affirmative grant of legislative authority to reach the matter, but because the Constitution prohibits it from exercising the authority in that manner.' Id., at 845."

"As footnoted (2) in United States v. Alfonso Lopez, Jr:

- "See also Hodel, 452 U.S., at 311 ("[S]imply because Congress may conclude that a particular activity substantially affects interstate commerce does not necessarily make it so") (Rehnquist, J., concurring in judgment); Heart of Atlanta Motel, 392 U.S., at 273 ("[W]hether particular operations affect interstate commerce sufficiently to come under the constitutional power of Congress to regulate them is ultimately a judicial rather than a legislative question, and can be settled finally only by this Court") (Black, J., concurring)."

..."The dissent of course resorts to the last, best hope of those who defend ultra vires congressional action, the Necessary and Proper Clause. It reasons, post, at 3–5, that the power to regulate the sale of handguns under the Commerce Clause, coupled with the power to 'make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers,' Art. I, §8, conclusively establishes the Brady Act's constitutional validity, because the Tenth Amendment imposes no limitations on the exercise of delegated powers but merely prohibits the exercise of powers 'not delegated to the United States.' What destroys the dissent's Necessary and Proper Clause argument, however, is not the Tenth Amendment but the Necessary and Proper Clause itself. When a 'La[w] . . . for carrying into Execution' the Commerce Clause violates the principle of state sovereignty reflected in the various constitutional provisions we mentioned earlier, supra, at 19–20, it is not a 'La[w] . . . proper for carrying into Execution the Commerce Clause,' and is thus, in the words of The Federalist, 'merely [an] ac[t] of usurpation' which 'deserve[s] to be treated as such. The Federalist No. 33, at 204 (A. Hamilton). See Lawson & Granger, The 'Proper' Scope of Federal Power: A Jurisdictional Interpretation of the Sweeping Clause, 43 Duke L. J. 267, 297–326, 330–333 (1993). We in fact answered the dissent's Necessary and Proper Clause argument in New York: '[E]ven where Congress has the authority under the Constitution to pass laws requiring or prohibiting certain acts, it lacks the power directly to compel the States to require or prohibit those acts. . . . [T]he Commerce Clause, for example, authorizes Congress to regulate interstate commerce directly; it does not authorize Congress to regulate state governments' regulation of interstate commerce.' 505 U. S., at 166.

"The dissent perceives a simple answer in that portion of Article VI which requires that 'all executive and judicial Officers, both of the United States and of the several States, shall be bound by Oath or Affirmation, to support this Constitution,' arguing that by virtue of the Supremacy Clause this makes 'not only the Constitution, but every law enacted by Congress as well,' binding on state officers, including laws requiring state-officer enforcement. Post, at 6. The Supremacy Clause, however, makes 'Law of the Land' only 'Laws of the United States which shall be made in Pursuance [of the Constitution]'; so the Supremacy Clause merely brings us back to the question discussed earlier, whether laws conscripting state officers violate state sovereignty and are thus not in accord with the Constitution."