When discussing the Constitution in general and the Supremacy Clause in particular, there appears to be some confusion as to what this means. So lets just look at the Supremacy clause.
Federalist Paper #33 (Para 6 and 7)
.........But it will not follow from this doctrine that acts of the large society which are NOT PURSUANT to its constitutional powers, but which are invasions of the residuary authorities of the smaller societies, will become the supreme law of the land. These will be merely acts of usurpation, and will deserve to be treated as such. Hence we perceive that the clause which declares the supremacy of the laws of the Union, like the one we have just before considered, only declares a truth, which flows immediately and necessarily from the institution of a federal government. It will not, I presume, have escaped observation, that it EXPRESSLY confines this supremacy to laws made PURSUANT TO THE CONSTITUTION;
PURSUANT TO THE CONSTITUTION. This is self explanatory and clear. Laws enacted must be PURSUANT TO THE CONSTITUTION.
........Though a law, therefore, laying a tax for the use of the United States would be supreme in its nature, and could not legally be opposed or controlled, yet a law for abrogating or preventing the collection of a tax laid by the authority of the State, (unless upon imports and exports), would not be the supreme law of the land, but a usurpation of power not granted by the Constitution.
Federalist Paper #78 (para 10)
....…every act of a delegated authority, contrary to the tenor of the commission under which it is exercised, is void. No legislative act, therefore, contrary to the Constitution, can be valid. To deny this, would be to affirm, that the deputy is greater than his principal; that the servant is above his master; that the representatives of the people are superior to the people themselves; that men acting by virtue of powers, may do not only what their powers do not authorize, but what they forbid.
Federalist Paper #27 (last para)
.....…the laws of the Confederacy [the federal government], as to the ENUMERATED and LEGITIMATE objects of its jurisdiction, will become the SUPREME LAW of the land; to the observance of which all officers, legislative, executive, and judicial, in each State, will be bound by the sanctity of an oath. Thus the legislatures, courts, and magistrates, of the respective members [the States], will be incorporated into the operations of the national government AS FAR AS ITS JUST AND CONSTITUTIONAL AUTHORITY EXTENDS… .....
It is clear that the Supremacy clause DOES NOT grant the Federal (or State) government the power to enact any laws it (they) wish. All laws enacted must satisfy each and every Article, Section and Clause, as well as the Amendments for it to be Constitutional and valid. Any law enacted that does not fulfill these requirements is null and void.
Many of the Federal firearms laws have used and abused the Commerce Clause as it’s Constitutional Authority. So be it. However, getting this law past the commerce clause does not make the law valid as it goes against the 2nd Amendment. And the 2nd Amendment is the Supreme Law of the land as stated in the Supremacy clause, Article 6.
Other sites of interest....
War on Guns, notes from the resistance