The terrorist, a 28-year-old Australian man, wrought havoc in Christchurch in an attempt to show that nobody is safe anywhere, especially in a sleepy South Island town. He became radicalised online and preached white supremacy and hate speech. This episode zooms out again to examine the shooter's backstory. We employ the help of international terrorism expert Amarnath Amarasingam on understanding how people become radicalised in the first place and how social media and Trump have played a role in mainstreaming extremism.  CREDITS Reporter & writer: Ashleigh StewartScript & story consultation: Popsock MediaProducers: Bashar Najjar and Basel Anabtawi 'Our Darkest Day' is a Rising Giants Network production.  See omnystudio.com/listener for privacy information.