I went home for lunch on April 20, 1999. I’m not sure why I turned on the TV, but I did. And once I had, I couldn’t believe the story that was splashed across every channel. I’m not sure what I was hoping to watch, but I remember vividly what I did see: the image of countless emergency vehicles and police cars, lights flashing, surrounding a Colorado high school on the suburbs of Denver.

Those images were underscored by the anxious voice of the news anchor, barely concealing her emotions, as she detailed how two teenage boys had done the unthinkable. They had gone into their school and begun shooting their classmates and teachers before turning their guns on themselves.

I sat there, in the sparsely furnished living room of the house I shared with two of my friends in Arlington,Va., with tears streaming down my face glued to the TV.

The tragic event at Columbine was nothing short of a massacre. It left 12 students and one teacher dead, 27 wounded and so many more emotionally scarred. Across the nation, we mourned for the families who had suffered such a horrendous lost. We hugged our children, our sisters and brothers, our nieces and nephews, that much tighter that night and for many nights thereafter. But other than triggering a few changes in school security, what exactly did this horrible event teach us? For many of us, the memories faded as we faced new horrors in our ever changing world.