I had my first male teacher in fourth grade at Cayuga Heights Elementary outside Ithaca. That was back in 1960. I don’t know if he was a WW II veteran, but I DO know you did’t act up in Mr. Razzman’s class.
He never threatened to shoot any of us, but he had firm control of that class. Of course, we were docile suburban kids and, if anybody DID act up, Dad would take care of the problem when we got home. So we had the double threat of Mr. Razzman and Dad.
In the 50s, had a WWII-vet ex-Marine in my public school in a slightly rough area of NYC. Nobody messed with him.
He was famous for making disruptive kids bend over in front of the entire lunchroom (because lunch was their favorite time for harassing other children) and then kicking them in the backside while we all cheered.
It worked. Granted, a little harsh...but I betcha none of those kids ever went to jail, if only because he made them look ridiculous and we were laughing at them.
Dads are extinct in many Cultrals as of late