When I was at primary school, the best teacher there had to retire when they stopped being able to use corporal punishment. She rarely did but the option was there and she ruled by fear, will seem alien now but when you were under threat of the shakermaker (she would hold you by the shoulders and shake you) you did as you were told
I don't think schools should be able to physically discipline and as a parent I have never smacked my son BUT there is a genuine lack of respect from some kids now.....although I may just notice it more now I'm older and can the classic "in my day...." lines