After Columbine, Dave Cullen swore he would never write about a mass shooting again. But over the next 20 years, he realised that he and other journalists had a duty to destroy the deadly myths they had helped create.
As I drove down Highway 6 toward the Rocky Mountains on 20 April 1999, hoping to find this high school I had never heard of
in Columbine, where shots had been reported but no injuries, I had no conception of what I was about to witness. What was happening inside that high school was unimaginable. What it ignited was far worse.