On July 20, 2012, twelve people were killed and fifty-eight wounded at a mass shooting in a movie theater in Colorado. In 1999, thirteen kids at Columbine High School were murdered by their peers. In 2012, twenty children and seven adults were killed at Sandy Hook Elementary. Thirty-two were killed at Virginia Tech. Twelve killed at the Washington Navy Yard. In May 2014, after posting a YouTube video of retribution and lamenting a life of loneliness,...