AKA TRUMPISM:

Clearly, no one who commits mass murder is mentally well or emotionally stable. But the assumption that mental illness begets or predicts heinous acts of violence is false, according to experts on school shootings and mass violence. Mass shooters' desire for death and destruction, experts have found, stems from a variety of circumstances and is rooted in entrenched grievance, despair, and anger, regardless of whether they experience symptoms of mental illness.

"No mass shooter is a mentally healthy person, but to blame mental illness as the cause of mass shootings fundamentally just isn't supported by case evidence and by scientific study," said Mark Follman, a journalist and author of the new book "Trigger Points: Inside the Mission to Stop Mass Shootings in America."

A decade ago, Follman (along with this reporter) created the first open-source database documenting US mass shootings. Far from having delusional thoughts or hallucinations, most mass shooters believe they are making reasoned and calculated choices based on real or perceived injustices in their lives, Follman and other experts contend. Their violent thinking is often validated in the dark corners of the Internet, where they are radicalized even further. Some study other perpetrators and try to emulate them.

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