Because states cannot ignore the US Constitution or the 2nd amendment. States also cannot take away your right to free speech or force a religion on you.
Actually, they could.
After ratification, several states had state supported religions.
They were never challenged by the Federal Government.
They were long gone when the 14th was ratified.
.
But not because they were challenged.
The states themselves chose to write them out.
Clarence Thomas recently hinted that such support today would be constitutional.
Considering current case law I would seriously doubt that.
.
Yes, I get that.
But no matter what you doubt, that a SCOTUS judge would hint at such a thing informs that the crapp associated with the supposed "separation of church and state" started out as a federal thing only.
There is no difference in the 2nd.
Most states put that same language in their constutitons. What did they know that we don't ?
What gets me, in the 1947 ruling Black cited Jeffersons letter instead of the incorporation doctrine in one of the earliest rulings on church and State.
As far a the 2nd goes, this is what the TX Constitution says.
Sec. 23. RIGHT TO KEEP AND BEAR ARMS. Every citizen shall have the right to keep and bear arms in the lawful defense of himself or the State; but the Legislature shall have power, by law, to regulate the wearing of arms, with a view to prevent crime.
.