Thank you. You were paying attention when you read my post. The child was asking the very valid question why violence is OK sometimes and not at others.
Actually, the kid was asking why it was OK for his father to "smack" him. Answer: It's not. Spanking, done right, is as different from "smacking" or "hitting" as working on the hinges to fix a door is different from kicking it to open it.
I love the way that every single anti-spanking poster on this thread refuses to discuss or even acknowledge the difference. It's like watching an echo-chamber full of YECists agree that we cannot have come from monkeys because there are still monkeys.
For the record, some of us are not "anti" or "pro" and can consider the difference between "smacking" and "properly applied spanking" and still explore a child's ability to tell the difference as well as our own.
I am quite truly and honestly not "anti" spanking. I have no visceral reaction and very little emotion on the subject. It is calculated pragmatism to me. When I see someone "smacking" their kid in public, I don't actually think, "what a cruel person!" I more often think, "I don't expect that'll work as well as you want."
I am truly a student of the child's reactions, not my own memories and base my opinion on that. (Why do I claim that? Because I was spanked hard, angrily and with 2x4s and I don't have an angry memory of that, just a sense that it was ineffective.)
O is right that there are kids whose behavior is much further out on the curve. Some are downright sociopath. This is true and real.
And I would counter (except in the case of the clinical sociopath), that earlier in those kids' lives different disciplines could have created different results. Once they have been exposed to the behavior that they should not repeat, they will be harder to guide. Not impossible, but much harder. (Still, I don't condemn reactions like the one O gave, I just don't think it's the only one, and I'm sure she doesn't either.) The situation of dealing with a post-spanking child (or more dramatically, a post-trauma child) is so different than deciding whether spanking itself is effective that it would need to be a separate discussion altogether, IMHO.
I do believe from observation that kids do mimic to others what was done to them with a very natural disregard for what someone else is entitled to do that they are not. Kids want "equal" not "fair" in general. And so leaning to the side of doing to children only what children are allowed to do to others will produce the fewest deviations from them later.
Again, from a coldly pragmatic standpoint. Every single thing that a parent does that a child may not brings up the question, "why you and not me?" It always comes up, whether they verbalize it to you or not. Why can you have wine and I can't? Why can you shower and I have to bathe? Why do I have to put down the toilet seat but you don't have to put it up? Why can you do your chores in the evening, but I have to do mine in the afternoon? Why why why. They always think it, sometimes ask it, when they encounter a case when they are told "some for me and none for thee." And if they aren't told that, they will assume that what you can do, I can do, too. Until they do it and are told they mustn't.
Spanking is not magically different in this regard. If you yell at your child when frustrated, that child will use yelling when they are frustrated. If you say please and thank you every day, the child will develop that, too. If you spank a child, the child will think spanking is the thing to do when someone misbehaves, and you'll be pressed into explaining why not after you see them. In my experience.