To a degree I do agree. There should be a line that the parents shouldn't cross and as long as they don't cross it and ensure the child only learns from it then it's okay.

I disagree, if the parent can make sure the child learns something by spanking them, then it shouldn't be considered a bad thing.

Spanking has proved that it is a very effective form of discipline. I can from experience that it is true because I'm fairly disciplined and I was spanked. Of course, this isn't a perfect disciplinary option because some people that were spanked have turned into brats. I believe that it can be a good and bad thing unless you can make it so the child learns from it. The child has to know that there is a reason for him or her to be spanked, otherwise he or she will think of it as bad parenting and will do the same to his or her children and so on.