I think that without the computer trail of AL, there will never be a way to know if his inclination to this degree of violence should have been caught in time to somehow prevent it. Lots of people, unfortunately, have all kinds of disorders and conditions that cause them to be anti-social, even hermit-like, and to take on OCD characteristics and lose the ability/desire to communicate in a "normal" way.
I do wonder, though, and will never know, if he would have gone this route if not for the gun training and the using by his mother of shooting as a hobby. Other than the guns, he reminds me a lot of my brother, who is now in his forties, and nursing his various mental illnesses and obsessions quietly in a room in the family home. But then we never had a gun in our home, or anyone who hunted, or much tolerance for guns at all.
