David Katz, The Madden Tournament Shooter, was a tragedy waiting to happen. Born with a likely predisposition to mental illness (possibly on the autism spectrum plus major depression or schizophrenia), his life took a turn for the worse when his parents divorced and he fell through the cracks. Though he received some psychiatric treatment, it was obviously not enough. Depressed and angry, his obsession with violent video games flourished-until it was no longer a game-but very real when he went on a shooting spree at a Madden Tournament and killed and injured other gamers. Today's guest, Lt. Colonel Dave Grossman, bestselling author of Assassination Generation: Video Games, Aggression, and the Psychology of Killing, is the world's foremost authority on these issues. After Parkland, he was summoned to the White House by President Trump to talk about the impact of video games at a meeting with representatives from the gaming industry. One thing we can agree on: the shooting must stop.