In all the diaries and comments I've read, I haven't seen this come up, and I'm curious to see what the response might be.
If you're a responsible gun owner, what provisions do you/should you make so that the guns you're responsible for don't fall into the hands of people who aren't responsible? What disposition have you made for your guns on your death/in your will? Have you taken steps to make sure they are going to be disposed of, or turned in to a reliable agency, or given to someone you trust to be as careful of them as you are?
If you're married, have you considered what the disposition would be in case of a mutual disaster? Do the two of you have a single inheritor you can trust to keep the gun(s) responsibly?
If you're for regulation: If we're going to regulate guns well enough to keep even a little control over where they end up, it strikes me that the circumstance of the death of the current owner needs, somehow, to be included in the mix. For full tracking, gun ownership would somehow have to be linked to the Social Security database, so that on report of a death, some agency like the local police would be notified that a gun or guns owned by the decedent would need to be either re-registered or confiscated. That would be contingent on all gun sales or resales having to be fully registered, which is one of the points that gun safety advocates are making anyway.
If you're against regulation: I think it becomes even more necessary to make sure your undelineated real property, including guns, is covered as well as possible in your will. In the absence of clearly willed inheritance, who ends up with that property? Do you know? Do you trust them to be responsible? If not, what alternate arrangements have you made, and have you checked to see whether they're likely to hold if there are squabbles over the inheritance?
I don't have any answers here, only questions, but I think they're worth asking.