The Tennesee church shooter, James Adkisson, sounds like many other mass killers in this article from the Knoxville News-Sentinel. In the USA Today, the note he left was described as “irrational.”
In reading the Sentinel article, you get the sad picture of a person who was in need of mental health treatment but did not get it. His ex-wife attended this church which may have been a motive in the shooting.