There is the small matter of the supremacy clause in the United States Constitution, in case no one in the Missouri General Assembly has bothered to read it:

Article VI
….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, anything in the Constitution or laws of any State to the contrary notwithstanding….

And, uh, the United States Supreme Court gets to decide what is constitutional, not the Missouri General Assembly:

Marbury v. Madison, 5 U.S. 137 (1803)

….It is emphatically the duty of the Judicial Department to say what the law is. Those who apply the rule to particular cases must, of necessity, expound and interpret the rule. If two laws conflict with each other, the Court must decide on the operation of each.

If courts are to regard the Constitution, and the Constitution is superior to any ordinary act of the legislature, the Constitution, and not such ordinary act, must govern the case to which they both apply….

In the Missouri General Assembly, three years ago:

HB 2196: blah, blah, guns, tenther drivel, blah, recycle, blah, stir…

The sponsor in 2016 was Representative Jeff Pogue (r).

Five years ago:

HB 1556: because we can never have too many tenther gun bills in the Missouri House

Six years ago:

HB 162: Tenthers and guns, what could go wrong?

Nine years ago:

HJR 88: a veritable thesaurus of tenther drivel

A bill introduced yesterday by Representative Jeff Pogue (r):

HB 786
Establishes the “Second Amendment Preservation Act”
Sponsor: Pogue, Jeff (143)
Proposed Effective Date: 8/28/2019
LR Number: 1046H.01I
Last Action: 01/31/2019 – Introduced and Read First Time (H)
Bill String: HB 786
Next House Hearing: Hearing not scheduled
Calendar: HOUSE BILLS FOR SECOND READING

Some of the (familiar) bill language [pdf]:

…(3) The limitation of the federal government’s power is affirmed under the Tenth Amendment to the United States Constitution, which defines the total scope of federal power as being that which has been delegated by the people of the several states to the federal government, and all power not delegated to the federal government in the United States Constitution is reserved to the states respectively or to the people themselves;

(4) If the federal government assumes powers that the people did not grant it in the United States Constitution, its acts are unauthoritative, void, and of no force…

Blah, blah, blah, tenther drivel, gun stuff, blah, blah, blah, stir…

Willful ignorance of two centuries of American history gets us to where we are today.