There are 19th Century Supreme Court decisions stating that the 2d Amendment is a restriction only on the federal government, not on the States. Heller, in a footnote, mentioned these cases and said their validity was not before the Court because Heller involved federal (D.C.) law.
You and I went over this yesterday. I posed a few questions, you didn't answer after about half an hour (but you were active on FR), and you never responded when I answered for you.
You: Presser said that the 2nd Amendment is a restriction only on Congress, not on the states.
Me: Did it say anything about the right of the states to prohibit the people from keeping and bearing arms?
Answer: Yes, it did. This is what it said:
It is undoubtedly true that all citizens capable of bearing arms constitute the reserved military force or reserve militia of the United States as well as of the states, and, in view of this prerogative of the general government, as well as of its general powers, the states cannot, even laying the [second amendment] out of view, prohibit the people from keeping and bearing arms, so as to deprive the United States of their rightful resource for maintaining the public security, and disable the people from performing their duty to the general government. But, as already stated, we think it clear that the sections under consideration do not have this effect. Presser v. Illinois, 116 U.S. 252 (1886)
Me: What was the general nature of the statute at issue in the Presser case? What action was Presser arguing was protected by the 2nd amendment?
Answer: The statute at issue was one that required obtaining a permit before conducting a parade on public property. Presser argued that his parade didn't need a permit, because his parade was made of up citizens bearing arms, and therefore, his parade was protected by the 2nd amendment to the US Constitution.
I think the full story is interesting to readers, and for the most part, the complete picture is new to them, as well. In part because folks like you tend to tell half the story.