Very sorry to hear about this, Dave, and sorry for the community of Knoxville.
That he believed what he believed, read what he read, and did what he did still isn't surprising. There is a large undercurrent in this country full of people on the verge of doing exactly as he did with only the slightest human impulses holding them back. If this shitbag wanted to look deeper into what's actually "destroying the country", he should have examined the recipe of guns + religion + fear & ignorance. It's responsible for a thousand times the bloodshed of "churches admitting gays".