No, the reality is that kids are supposed to think that there are two people in the world that they can trust, and trust not to hurt, shame or make them afraid - their parents. Your use of violence opens them up to choosing abusive relationships in future because they’ve been taught that ‘trivial’ fear and violence are a part of close relationships.
I disagree that that should be what children are supposed to think. I prefer it if they use their childhood to actively figure out if it they love me, what love and trust means, and if it works for them to have a relationship with me rather than for them to have unrealistic assumptions about personal relationships.
ETA: I'm not sure what you mean by using violence opens them up to abusive relationships. Once children are old enough to reason with and there is less requirement for immediate action as they can link the delayed punishment of being grounded or having something taken away to their earlier action or behaviour, slapping becomes a pointless thing to do. Other consequences are more effective but still not time-consuming to implement. Plus I agree that the older you get the more autonomous you feel from your parents, therefore the more humiliated you feel by being physically punished especially as it doesn't particularly hurt - so I think slapping an older child - anyone age 7 or over - is not effective.
An adult is not responsible for another adult and is not expected to control the other adult - so they can walk away from the relationship rather than slap another adult. I would call the police if my husband ever slapped me and I would expect him to call the police if I ever slapped him. I don't equate us being hit as children by our respective parents with us having the right to hit each other in an adult relationship, when we have the option of walking away if the other person behaves in a way that makes life unpleasant.
I am also less interested in my children feeling hurt, shamed or afraid of a trivial slap and more interested in them knowing that I expect them to co-operate or there will be consequences. If the slap does not work as a consequence then I have no interest in using it.
My children were aware they could always take their chances with social services and the care system if they felt they could not cope with the trauma of consequences at home.
I'm curious to know how this smacking ban would be enforced - if I went to prison for a trivial slap, which is fine with both me and my husband, is the public policy logic that the children would be less traumatised by being brought up in care and not going to a private school while we are in prison rather than living at home and going to a private school and receiving a trivial slap?