I'm sure there must be some exceptions to the rule.
I haven't googled it to find exceptions but I'm sure they exist.
However, every school shooter that I can recall hearing about here in America has been male.
Why do you think that is, and do you think testosterone plays a large role in it?
(I remember living in a foster home that was a farm, and much of the bad behavior seen in bulls, was prevented if you removed their testicles at a young age. I'm not suggesting that is a solution, but interesting nonetheless how much having balls affects a mammals behavior.)
Public education in America is controlled by the liberal left. A school being the target, implies that the psychological damage done to the shooters appears to have a connection to liberal education and indoctrination; school. He is striking back at school and their next zombie army.
Among the many things that the children are indoctrinated in American public schools is blaming males, especially white Christian straight males for all the woes of the world. Some boys transform into the self for filling bad boy image suggested by the propaganda.
An analogy is if a parent called a child, stupid, enough times, some children will begin to think they are stupid. Some children will even try to please the adults by deliberately trying not to be smart. All the left wing adult led negative propaganda, has had a long term adverse impact on some of the boys.
In liberals education, girls are placed on a pedestal so there is no need to strike back. The propaganda say they are the innocent victims. That is their programmed role. A female cannot be a male-o-phobe no matter how many times she recites the propaganda that stereotypes males in bad light. This lopsided illogic is part of the indoctrination process designed to conflict with justice and create backlash.
Only a boy will be called phobic if he tries to be reasonable about any of the lopsided propaganda and revisionist history. The boys are implied to be damaged, from day one, just due to being born a male. Doesn't feminist propaganda say that males are destines to be predators due to their DNA? You get what you ask for if you start his young enough.
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