Mass Shootings Have Become a Sickening Meme. Murders, Attempted Murders and Homicides, Hate Crimes, Social Media, Chabad of Poway (Poway, Calif, Synagogue), Christchurch, New Zealand, Attack (March 2019), Pittsburgh, Pa, Shooting (2018), Poway (Calif), Terrorism, Chabad of Poway Synagogue Shooting (2019)