Whenever we talk about mass shootings I always make the argument that the weapon used isn't particularly relevant. It's just a tool. If one tool is unavailable, another will present itself. The problem isn't the gun, it's a combination of mental health issues and the desire to commit such an atrocity in the first place.
Still, those who seek to ban firearms always scream "gun control" and bring up the unmitigated horror of Sandy Hook. While other incidents fade into history, Sandy Hook - because of the innocence of its victims - remains fresh. It is, to this day, every parent's worst nightmare.