I agree with it in the main.
All of my DC have been taught not to throw the first punch but to make sure they've thrown the second.
DD was walking home from the shop (yr6) and some nasty cow from the secondary school started on her. Following her, pulling her bag off her back, grabbing her shoulder. This had followed a week of low level name calling. She poked DD in the face with her finger whilst shouting in her face, mates all crowded round laughing.
DD lumped her on the nose and put her arse on the ground.
None of them have looked at her twice again. Bonus points that the little cow landed in a puddle.
Teach your kids to throw a defensive punch. These two knuckles hurt them (main two), these two knuckles hurt you (two little knuckles). Fists up and swing for their nose. No point in hitting the cheek.
Emotional bullying, excluding, name calling, stealing doesn't warrant violence. If someone hits you, you bloody hit them back.