Regardless of what I do in my home, though, I think that every parent has the right to make the decision for themselves as to whether to spank, and for what reasons. Abuse should not be tolerated, though.
It teaches your child that you can overpower them just because you're bigger. Plus, it sends a mixed message. How can a parent teach a child not to solve problems by hitting, when the parent is hitting them? This is my fundamental problem with spanking. But it is very difficult to unlearn what I learned growing up. I have to work very hard at it.