“We are therefore persuaded that the Due Process Clause of the Fourteenth Amendment incorporates the Second Amendment and applies it against the states and local governments.”
This may be beside the point, but I’ve never understood the incorporation principle. What does the due process clause of the 14th amendment have to do with the specific enumerations of the Bill of Rights? Nothing. Due process is all about PROCESS. Free speech, gun rights, etc. are not procedural issues; they are substantive issues.
That being said, you don’t really need the incorporation principle to imagine that the protection of gun rights extends to the states. Unlike the provisions of the first amendment, the second amendment doesn’t specify that Congress should make no law, etc. All it says is that the right of the people to keep and bear arms shall not be infringed.
Since the Constitution, in addition to enumerating the powers of the federal government, also denies certain powers to state governments, we can perhaps assume that the second amendment named the infringment of gun rights as one of the powers denied to the states. Certainly, I don’t see anything in the second amendment that says it doesn’t apply to the states.
Due Process has two parts: Substantive and Procedural. The idea is that without substance, procedure is moot. (WAY simplified, but you get the idea.)