The people, then, sir, erected this government.  They gave it a constitution, and in that constitution they have enumerated the powers which they bestow on it.  They have made it a limited government.  They have defined its authority.  They have restrained it to the exercise of such powers as are granted; and all others, they declare, are reserved to the States, or the people.  But, sir, they have not stopped here.  If they had, they would have accomplished but half their work.  No definition can be so clear as to avoid the possibility of doubt; no limitation so precise, as to exclude all uncertainty.  Who, then, shall construe this grant of the people?  Who shall interpret their will, where it may be supposed they have left it doubtful?  With whom do they repose this ultimate right of deciding on the powers of the government?  Sir, they have settled all this in the fullest manner.  They have left it with the government itself, in its appropriate branches.  Sir, the very chief end, the main design, for which the whole Constitution was framed and adopted, was to establish a government that should not be obliged to act through State agency, or depend on State opinion or State discretion.  The people had had quite enough of that kind of government under the Confederation.  Under that system, the legal action, the application of law to individuals, belonged exclusively to the States.  Congress could only recommend; their acts were not of binding force, till the States had adopted and sanctioned them.  Are we in that condition still?  Are we yet at the mercy of State discretion and State construction?  Sir, if we are, then vain will be our attempt to maintain the Constitution under which we sit.

But, sir, the people have wisely provided, in the Constitution itself, a proper, suitable mode and tribunal for settling questions of constitutional law.  There are in the Constitution grants of powers to Congress, and restrictions on these powers.  There are also prohibitions on the States.  Some authority must, therefore, necessarily exist, having the ultimate jurisdiction to fix and ascertain the interpretation of these grants, restrictions, and prohibitions.  The Constitution has itself pointed out, ordained, and established that authority.  How has it accomplished this great and essential end?  By declaring, sir, that “the Constitution and the laws of the United States made in pursuance thereof, shall be the supreme law of the land, any thing in the Constitution or laws of any State to the contrary notwithstanding.”

This, sir, was the first great step.  By this the supremacy of the Constitution and the laws of the United States is declared.  The people so will it.  No State law is to be valid which comes in conflict with the Constitution, or any law of the United States passed in pursuance of it.  But who shall decide this question of interference?  To whom lies the last appeal?  This, sir, the Constitution itself decides also, by declaring, “that