My conservative kids would have not want their dad fighting their battles and would be perfectly secure in handling this teacher.
There was a time, many years ago, that I would have agreed with you, and my kids, going to Catholic grade school in the 70's NEVER had to face this kind of insanity.
Today, with the insane "teachers" I'm not so sure.
If I were a parent today, I may be arrested for what I believe is correct action.