You're unwittingly making the case for not physically punishing children.

As adults we aren't struck for our transgressions.. If we're abusive on the job and corrective instruction doesn't fix it, our employment will be terminated. If we libel someone and don't correct or retract the statement, we may face a monetary penalty. If we vandalize a building, we might be assigned to community service. If we speed we pay a fine. These are the appropriate consequences for the misbehavior. The practice of receiving a physical punishment for our legal violations ended long ago. So if we've decided that misbehavior by adults doesn't warrant physical punishment, by what standard could we conclude that a mere child deserves it?