Tumor-
I have two daughters.
We've been down this one before. I will spank if necessary and won't apologize. And, as much as some here would paint me as a totalitarian brute because of it, it just isn't so. Spanking isn't the first recourse for me, but it is an option, and my daughters both know it.
Punitive parenting teaches the child to fear you and/or authority figures and hide thier actions from them, not necessarily to stop the actions.
This is '60s hippy crap, and I think that every time I see it. I don't mean to offend with that comment, I know how you feel about it, but this totally ignores the societal norm. Society will first condemn an action of an individual, but eventually there is a punitive recourse that follows uncivil action.
Human beings are greedy and selfish by nature, make no mistake about it. We want what we want, how we want it, when we want it, where, etc. One of the measures of maturity might be the ability to deny that basic instinct for the sake of others. Small children for the most part simply don't possess that maturity, nor are they born with an innate understanding of how a society works.
So... your two-year-old decides he wants the toy another child is holding... he pushes the child and takes it. You see the event. You say to your child, "Now give that back". You can even throw in "Please" if it makes you feel better. Your child clutches the toy to his chest, turns away, and runs. You chase after your child, catch him, and ask again for the toy. The child twists away from you and starts yelling "No! No!". What do you do?
1. If you let the child keep the toy, you are sending the message that it is ok to deny authority, because you eventually get your way if you are persistant enough.
2. If you take the toy back, aren't you teaching the child to fear you and/or authority figures and hide his actions from them, not necessarily to stop the actions?
You see, the mild swat on the butt isn't the issue, it's the way you view that child and his place in society. You could begin his entry into society by creating an atmosphere that is a reflection of that society (as in the way they learn the native language, through immersion), or you could create a bubble around him and protect him from society and the consequences of his actions. If you have a son that absolutely refuses to respond to all non-punitive (and I am using your term) forms of behavioral modification and corporal punishment is not on the table, what next?
Of course this doesn't matter a great deal to me... my daughters behave great, I've spanked them maybe ten times over the course of their combined nearly 18 years, and they are doing great in school and with friends. It all seems pretty simple to me.