@Meridis
Neither of the murderers were serial killers. They were mass murderers. Serial killers have individuals they kill or very small groups. Mass murderers kill as many as possible within a time frame. Timothy McVeigh, Dylan Klebold, and Eric Harris are not serial killers. And Ted Bundy, John Wayne Gacy, and Harold Shipman are not mass murderers despite the body count. Serial killers, as you said, don't need mental health treatment because they aren't mentally ill, just depraved. Mass murderers believe that they will bring on change or justice by there actions. There is definitely something wrong if you believe murdering people, who have little-to-nothing to do with the issue, will fix an issue.