Where Do You Draw The Line!?

KK
So I have been reading a lot of discussions about to spank or not to spank. And I got to thinking about a few months ago I saw a few videos of different children(different races, religions, countries) these children(in the three videos I've seen these children were all boys younger than 10) viciously attacked their parent (usually the mom) and these women sat there and did nothing in all three videos. The one that is etched in my brain is the one of a boy no bigger than 6 or 7 hitting and punching his mother while his sister sat in the other seat doing nothing and men and women just look in horror as this is happening...... Is this okay ? What would you do if you were in these women's shoes!? What type of punishment or reaction would you give!? 
Edit: I AM NOT ASKING ABOUT SPANKING SO DO NOT THINK ITS ABOUT THAT. I AM ASKING WHAT WOULD YOU DO IF YOU WERE IN THAT WOMANS SHOES AND WHAT TYPE OF PUNISHMENT OR REACTION YOU WOULD GIVE. 
Edit: this post is about the CHILDREN HITTING PARENTS. Some people keep commenting about spanking the children is bad. That's not it. The question is about the children hitting the parents.