Saturday marks two months since a school shooting killed 17 students and educators in Parkland, Florida. Since then, we’ve heard public outrage transform into ever more urgent calls for reforms to the nation's gun laws. Antoinette Tuff knows first-hand what it’s like to come face-to-face with a school shooter: On Aug. 20, 2013, she was working at Decatur’s Ronald E. McNair Discovery Learning Academy when a 20-year-old gunman entered with an AK-47 military assault rifle and 500 rounds of