Having a gun in a farmhouse in a rural place in Missouri does elevate the risk for suicide, but probably has limited or no effect on street or community violence. The availability of guns increases the chance of lethal outcomes. The vast majority of people who attempt suicide by means other than a gun go on to survive.
This is an issue which I feel is addressed relatively little in gun control debates, which is surprising considering that the number of people who intentionally shoot themselves annually in the US is about double the number intentionally shot by other people, according to CDC stats. A small majority of US suicides are done with guns.
I can't help but feel that having a gun in your home dramatically increases the risk of someone with suicidal inclinations going ahead with the act, whereas if they didn't have such an easily available and potentially painless option available they'd still be alive the following day when the feeling had passed.
I do find it hard to justify gun control on this basis philosophically, however. More deaths are caused annually in the US by drugs than guns, after all, and I have always argued against drug prohibition on the grounds that the state has no right to limit my freedom to protect me from my own decisions. Wouldn't the same logic apply to guns?
I'm also unconvinced by the gun-suicide link - even though it seems so intuitively obvious. The US certainly has a high suicide rate, but there are other developed countries, such as Belgium, where an even higher proportion manage to kill themselves despite strict gun laws (The UK's suicide rate, incidentally, is identical the the rate of suicide by means other than firearms in the US, but I suspect this is fortuitous coincidence).
There's no conclusion to this post, I'm just thinking aloud (or whatever the equivalent term would be for typing).