Ivan Lopez--Who Was this Shooter?

So now we are left with 4 dead, including Ivan Lopez the shooter.  Are we wondering, really asking who he is?  I wonder...don't we know but are afraid to say it out loud?  There is a point of view from John Donne and his classic poem, "No Man Is An Island"--we are all connected and each person's loss diminishes each one of us.  Easier to say with a poem?  Perhaps the truth is a bit much to bear that he was a victim also of circumstances that in the end he could not control.  PTSD, Iraq and the military is no place for me to be....  There is also the other point of view that others go through similar circumstances without taking the lives of others.  Nevertheless--he did. 

There is always one commandment we never think we could break--the one about killing.  Yet, as one commentator said, Lopez was dead before he pulled the trigger.  There is the third point of view--what does this matter to those who died and were critically wounded?  What response and obligation comes out of this event?