I do agree that in most cases, you can educate your kids without spanking, however, I can actually remember when I was a 6 or 7 year old kid and I can honestly tell you that sometimes, I didn't give a F**K about all my dad said until he pulled out is buckle.
And yes, he was explaining stuff, taking away toys, putting me in the corner... some days, I swear, the only thing that stopped me was my Dad's buckle.
Today, I don't think the same and comparing a kid to an adult is a false analogy. As a kid, I destroyed properties, played endless pranks, transpassed every where I could, lied, cheeted and beat up other kids. In the end, I was conciously doing these things as I knew all would be forgotten by law as long as I was under 16.
But before I could actually go on with my evil plan, my dad gave me a well deserved beeting (on my bum only) of a life time. You know what? It saved me. I stopped. I had realized that for my dad to respond to my actions with such force, I had gone to far. Especialy that he hit me for things that I had done while he was not aware of all the other things I did ...
If it had not been for my Dad hitting me like he did, I honestly believe I would have become a criminal, JW or not.