Okay, I will try again to make my position more clear.
Beating or punshing someone for any reason is something different then physical discipline like spankings and not okay at all. Especially against kids, but I would suggest to end a rela immediately if it is done to you and to strongly think about calling the police.
I don't support the physical discipline of minors or in parents to kids relations. This shouldn't happen, but also I think it was the norm for thousands and thousands of years and still is in most parts of the world. So even if I think it is wrong, I don't think that it normally causes massive psychological damage if it is done careful and transparent. If it is not done right, it's beating.
I also don't suppose the physical discipline in relationships if it is not consensual. But I think it was also the norm for thousands and thousands of years and still is in most parts of the world and I still think that it doesn't cause psychological damage for most, if it is done with care and transparent, which of course doesn't make it "right". If a partner lives in fear of what the other partner may do, it's abuse and the relationship needs to be ended immediately and it's likely a case for the police.
I support physical discipline in a relationship when it is consensual. Because I think it is a very close experience and an effective and fast way to handle incidents. Any non physical discipline has to be in place for long times, after a spanking is done, the issue is normally solved and this gives a very beautiful feeling of release. I think it must come with a good lesson before the spanking, so I can understand the reason of my partner, he has to ensure I understand his reason, but it is not necessary that I agree to his reason. A spanking without a prior lesson is not a spanking but beating. I also think that spankings should solve an incident completely, I don't like the idea of a series of spankings as a punishment, because then it looses it's character of solving an issue immediately.
I think that's how I would describe my position in detail.