Treating bullying as everyone's problem reduces incidence in primary schools

I always found it really frustrating that a "zero tolerance" policy to bullying seemed to disproportionately affect people who eventually fight back.

I would guess it's a combination of "nobody sees the first hit" (since your attention is elsewhere, of course) and that bullies get quite good at testing boundaries and thus know how to avoid detection.

But, really, it's truly frustrating that as I child I was bullied relentlessly, and when I finally took my parents advice and stood my ground, I was expelled from school (due to zero tolerance). Those bullies continued to torment some other kids, of course.

This is far from an uncommon situation, over the years I've heard many more scenarios like this.

Unpopular opinion, but most people who get bullied are a little "off", a little weird in some way that affects their likability. And this also affects the adults where even they judge the kid being bullied harder. For example if you are autistic and lack verbal skills, that's going to be seen as you lacking social skills. And obviously if someone got hit, who's most probable to have started it? Maybe the kid that "lacks social skills".