I find it dishonest to say that all hitting is bad, and that disciplinary spanking is violence. At the very least, quite the stretch. With all due respect I find it to be sensationally sensitive, too.
Football is violent, isn't it? Ban it, right? So's basketball. People get knocked over or pushed. All hitting is bad hitting, correct? Let's stop doing sports, because we're teaching children that violence is OK and should never be done for entertainment. Oh, and all war, too. If all hitting is bad, then all killing is the devil. And self-defense... And karate, judo, etc. All hitting/physical contact is bad.
All physical contact isn't bad if you enter and understand it voluntarily. Your analogy stinks.
But physical punishment from those you trust can break a child mentally. You could say you're lucky you weren't broken, but your kids if you spanked them or their kids kids who have all been passed the norm to hit all run the risk, simply because you couldn't use your brain to develop a better way to teach. It doesn't sound responsible, it sounds like teaching that bigger/stronger = boss/authority.
Spanking teaches children to love, respect, and obey their parents. Sometimes it doesn't work, but sometimes it is the only thing that will work. I think it is wrong and dishonest to try and paint spanking as some terrible thing, just as it would be wrong and dishonest to paint lack of discipline and spanking as some terrible thing.
It is not about teaching children that bigger/stronger = boss/authority. No, it's not. Please don't believe that lie. It's about children respecting their parents. There are quite a few people who love and spank their own children, but would never allow some stranger to do it. Why? It is because spanking is done between the parent, and his or her cub; not by some other person and your child.
I will spank my child when he or she does things that put him or her in danger, or others in danger, or when he or she does/says things that are disrespectful to the parent. You are the parent. You are not his or her little buddy. You need to remember that your child is not your equal while he or she is under your roof.
...do you allow your children to talk back to you? To whine and moan and scream and shout and curse you? If you let that happen, you're teaching your child to not fear you, and if he or she doesn't fear you, that child isn't going to fear or respect anyone else. Give an inch and they'll take a mile, my friend. If somehow non-physical discipline works for you, you're extremely fortunate.