Vivi. You're right. It's not okay to hit a child. Even spanking one of my children left me feeling more guilty than they felt contrite. Children are very aware of the power difference between adults and themselves, and they test it all the time. Sometimes the kids win (in 90% of the conflicts between me and my children, THEY win, because love and respect for my children is utmost in my heart, not discipline, and I get hell for that all the time from the other adults I live with).
In my culture it's traditionally up to the relatives (uncles and aunts) of the child's mother to discipline her children, because Lakota always wanted to preserve the close, loving relationship between the parents and their child, so no conflict between them was allowed. "It takes a village..." was something our people already had, they raised children as a group, not as individual, satellite families. Children were considered sacred. If a child misbehaved, they were shamed into good behavior, not hit or spanked. Of course, history and assimilation changed all of that.
So, I've been very reluctant to discipline my children, and relatives have stepped in to help (which hasn't always been helpful). The consequence, of course, is that I've been in legal trouble with the schools, social services, etc. because everyone asks me "Who is the parent?" I don't let my kids run wild or control me, but I do consider their opinions and try to parent with compassion, not with the need to be the supreme ruler of their lives.
I think our whole school and societal/parental system in the U.S. is bullshit, and that we put pressures on parents to overpower their children and "teach them who's boss", and if they don't, we punish the parents, AND the children, with social services, child "protection", and eventually prison. I've seen my children treated badly by their teachers because I'm not an aggressive parent, I don't push my kids to be like the other kids, or to conform to what schools imagine children should grow up to be because I don't believe all people should be exactly the same. All I can do is teach them that sometimes adults are screwed up, they have their priorities wrong, and as long as they feel like they are true to themselves, they didn't do anything wrong.