The doctrine of enumerated powers—the main restraint on the new government—was most famously stated by James Madison (No. 45): "The powers delegated by the proposed Constitution to the federal government, are few and defined. Those which are to remain in the State governments are numerous and indefinite." See: http://rootsofliberty.org/the-powers-delegated-to-the-federal-government-are-few-and-defined/

"The doctrine of enumerated powers stands for the idea that Congress has only those powers that are enumerated in the Constitution, which the people delegated to Congress when they ratified the Constitution or later amended it. Thus, the doctrine is of fundamental importance. It explains the origin of Congress’s powers, their legitimacy, and their limits. By virtue of the doctrine, the Constitution of the United States establishes a government of delegated, enumerated, and thus limited powers."

Article 6 clause 2 of the Constitution is known as the Supremacy Clause.  This clause in our Constitution is often misquoted, misapplied, and misinterpreted.  Those who support an overgrown and supreme federal power like to use this clause to beat the States into a powerless submission to every asserted federal authority.  Is that really what the designers of our Constitution meant when they placed this clause into the Constitution?

The Supremacy Clause reads:

"This Constitution, and the Laws of the United States which shall be made in Pursuance thereof;  and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding."

A plain reading of this text tells us several things:

This Constitution, shall be the supreme Law of the Land.

The Laws of the United States which shall be made in Pursuance to the Constitution are the supreme Law of the Land.

Treaties made under the Authority of the United States shall be the supreme Law of the Land.

The Constitution, through this clause has been established as the highest standard of Law regarding the federal government.  The Laws of the United States are below the Constitution.  The Treaties of the United States must be made under the authority of the Constitution.  As far as the federal government is concerned, there is nothing higher than the Constitution.

Alexander Hamilton explains the underlying principle of this clause in Federalist 78.

"There is no position which depends on clearer principles, than that 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."

James Madison explains in Federalist 45 "That the powers delegated by the proposed Constitution to the federal government are few and defined and those powers are to be principally exercised upon foreign affairs, such as war, peace, negotiations, and foreign commerce".

According to Hamilton, "when the federal government exercises powers that have not been delegated through the Constitution, the acts performed through that unauthorized power are null and void".   What that means is, if Congress passes a law and that law is not made consistent with the powers delegated by the Constitution, then that law is completely invalid. Thomas Jefferson reasserts this concept in the Kentucky Resolution of 1798:  "Whenever the general government assumes undelegated powers, its acts are unauthoritative, void and of no force."

The Supremacy Clause codifies this very principle;  "that any law made by Congress that is not made in pursuance to the Constitution, is no law at all".

A law made by Congress that is not made pursuant to the Constitution, is not authorized by an expressly delegated power, it is not the supreme Law of the Land and the Judges in every State are NOT bound by it.  The Supremacy Clause does not make every law of Congress, every act of Congress, every federal regulation, or every supreme Court opinion superior to State laws and State Constitutions.  It is the exact opposite.  The States agreed amongst one another to be bound by their mutual compact – the Constitution – not to subject themselves to every whim of their creation.

The Supremacy Clause, in fact, puts the federal government on notice that their every act is limited by the powers delegated through the Constitution.  The Supremacy Clause is NOT a limit of State authority, it is not a statement of supremacy of the federal government over the power of the States.

The Supremacy Clause tells those in the federal government that their power is limited by the Constitution and that the States do not have to submit to any imposed authority of the federal government that is not made consistent with the powers delegated by the Constitution, which the States themselves created.