The short version:
1. The shooter was bat____ crazy.
2. Everybody knew he was bat____ crazy.
3. Despite everyone knowing he was bat____ crazy and scaring everyone he came in contact with, nothing could be done, because ... he was a unique and precious little snowflake.
More casualties of the Community Mental Health Act of 1963.
Yup.
Note how teacher acts like he had NO CLUE.
Nobody Knew Nuffin....
My thoughts exactly.