Yesterday I read something from a gun guy speaking about how killing someone who breaks into your home at night could leave you troubled morally for the rest of your life. I personally could kill a number of those who break into my home by choice and still not be troubled morally anywhere near as much as I would be for just being part of an acceptance by the society for the killing of one person without a choice given to him or her like that school or the movie theater shooting as part of normal life. I don't see how it is possible to tolerate in any amount the absence of a choice to that level.
Another thing I saw recently that seems like a denial to the consequences of the gun situation we live in, is the level of regulation imposed by at least one state on , believe it or not, stun guns. This also reminds me of how those firearms commercials seem to generally advertise "gun and knife" not "guns" alone as if they are in anyway comparable.