It should be illegal for parent to hit their childrenii

A punch, hitting, a kick, a slap... What can this physical punishments could cause in a child of two, five, thirteen, or sixteen years old? Do these physical punishments teach something to them? What do you think they could learn with all of this? Respect or fear?
Is true, some parents lose their minds and don't think what they are doing, some of them are just mad and they can't control themselves, some of them were hardly punished by their own parents and they think that's the only way to solution their children's behaviors problems, some of those parents think that sometimes is necessary a little slap to control their kids, and despite I think physiological violence is worse than physical, is not a subject we must ignore at all.
If we think of ways of teaching in 50' to 90' is all conductive, and every time the student didn’t do what the teacher wanted, the student had to pay consequences, that's why I think our parents and their parents don't understand and can't get other ways to express anger or control their kids, and for worse, they are not able to dimensionate the damage their are doing do their child or what could the kid be into, such things as drugs or alcohol to "get away" from their houses.
I strongly believe that it should be illegal for parent to hit their children, because now there are new ways to teach and for let anger escape from ourselves, there is breathing exercises, communication, professional help, etc.
We don't want to see anymore cases like the man who almost kill her baby of almost a week of life, because he wanted to have a boy, not a girl. That are the kinds of things that proves us there are not qualified people to have children, so parents can control themselves or think two times what they are doing before they think if they want to have a baby.