The problem with determining who could be a school shooter

In the wake of school shootings at Columbine, Jonesboro, Santee High School, and at other venues, the FBI developed a checklist of signs to look for to determine jut who might potentially take a gun and shoot up a school.
I thought about that checklist following this week's arrest of five Riverton High School students who allegedly were planning to shoot up their school.
When I was teaching at Diamond Middle School, I administered the FBI test to my classes. What we found is that nearly 90 percent of the students (and the teacher) fit the mode of a school shooter. The guidelines included everything from people who had had dramatic upheavals in their lives (and at that time, I had forged ahead with a decision to leave journalism after 22 years and go into education), to enjoying heavy metal music. I had numerous students who had a fascination with Hitler, none of them worshipping him that I know of, but merely caught up in World War II, just as people in all walks of life have been since the war ended in 1945.
Ultimately, the FBI test was an exercise of futility, and that is the scariest problem that faces school and law enforcement officials. While there are warning signals when students might cause problems, unfortunately, there is no surefire way of seeing into a person's soul.