Can anyone seriously believe that King's message of nonviolence, aimed at sometimes violent people with legitimate grievances, has any relevance to an insane shooter? That Dr. King's soothing words would calm the storms in the mind of a paranoid schizophrenic? It is nonsense.
It reflects the authors' persistent mistaken belief that the shooter was acting out our sometimes vigorous political discourse, in spite of all the evidence to the contrary. They have called into question their own sanity.
