Does paranoia count as mental illness?
I saw my cousin yesterday for Xmas. Apparently, she's going off the deep end with this fiscal cliff, bad economy, tightening of the middle class, etc. and is convinced her home will be targeted when the 'class warfare' breaks out, as they have money and the husband is away all week.
She's talking a loaded weapon with a 30 shot clip in just about every room. Not locked away, not keeping the bullets separate from the guns, and debating not keeping the safety on. Her though is optimize response time if soemeone breaks in.
She also has 3 young kids who will be bound to find them when they are snooping around to see what Santa or the Easter bunny will bring. There's just so much that can go wrong. I can totally imagine junior finding it, showing it off to his friends after school one day, and them fooling around with it just right and someone gets shot.
This doesn't address mass murdering crazies, but it's on topic. A lot of gun related injuries/death could be avoided by a little responsibility and safety.