I wouldn't say spanking is an expression of love (you really need to have fundy word warp fully engaged to equate violence with love), but there are moments where the most effective way to gain a child's attention is to smack them right hard on the ass.

I'm quite willing to accept I lack parenting skill, but I have a hard time believing that my lack of skill has anything to do with the scattered attention and lack of impulse control common to 4 and 5 year olds that ends up in the total breakdown of social controls and communication, usually leading to me abusing striking my child. But I think we can all agree that someone who suggests "When children challenge defiantly, you must win conclusively" is not someone who you ought to be taking child-rearing tips from.