Keep in mind that the Bill of Rights simply enumerates some of our Rights. Just because a Right isn't listed doesn't mean it doesn't exist. For instance, you have a Right to a trial by jury, regardless of whether or not it's actually listed in the Bill of Rights or in any state constitution.
Likewise, you also have a Right to travel, even though it's not listed in the Bill of Rights.
The way I understand it, the 10 items mentioned in the Bill of Rights were so important, that some of the Founders wanted to put them into the Constitution. This was the blood price for getting states wary of federal power to accept the Constitition.
Also remember that according to Jefferson, the primary purpose of gov't is to protect our Rights. And since the Constitution is the supreme law of the land, the federal gov't has an obligation to support it, using force if necessary, when it is under assault from any "foreign or domestic enemy".
I forgot to include that he argued it from a "states rights" point of view. That if your state had no equivalent of the Second Amendment, then you're SOL with respect to state laws violating your RKBA.