What would be the harm?

[The Grand Nudger]

If you're looking for what realists ground their moral systems in, it's just not the thing you thought it was, and intuitivism is the very first stop.  It's laying there under the notion of an observed fact, any observed fact, in and of itself.  There are other stops on that line, but I couldn't begin to establish any of them, anyway, if you have an issue with facts. It doesn't require that you concede some argument over the nature of morality to concede that intuitivism is at least as compelling and at least as rational an explanation of harm as it is of anything else. It may not be enough for you, it may not be enough for me, but it is sensible. There's nothing obviously wrong with it, no fallacy in it's construction, etc. You'd have to refer to intuitivism, yourself, if I asked you similar questions about the system you're using to object to intuitivism, ultimately.

Take it away, again, webster.

: physical or mental damage or injury : something that causes someone or something to be hurt, broken, made less valuable or successful, etc.

• No harm was done.
  
• I never meant to do/cause you any harm. [=I never meant to harm/hurt you in any way]
  
• They threatened him with bodily harm.
  

[+] more examples

Yes, I do think that you dismiss it out of a lack of satisfaction, particularly in that people have an idea of what an objective morality would be that is entirely more, and more satisfying, than what it actually is. I don't think I've misunderstood any of your objections, I think that you misunderstand what moral theorists are discussing, and the related but distinct subjects that you've conflated for each other, and as though one created some necessary and troubling state of x for the other. We could go over all of them, again, if you like. Or, you could point to some specific thing that really irked you and I'll just say it again.

Here, I'll add a new one. A lion or a flesh eating bacteria most certainly wouldn't care whether or not I have a wound..but I'll still have one..I'll still have been harmed. Is there some objection you'd like to field to this? You're confusing agency and compulsion and caring, again, for the basis of both harm and objective moral propositions. That is, again, simply not what realism..or I, am talking about. I could, ofc, offer you many ways that realists handle those other things, but they are not the base of the realists moral position.

That something can be subjectively valued does not mean that the thing subjectively valued cannot be an objective thing. There is no valid inference from one directly to the other. It gives us reason, ofc, to go over our moral propositions to see if the specific example is, properly and meaningfully, ethically subjective..but it simply doesn;t help to establish that -all- moral values are subjective because some can be or because many are subjectively valued. Realists also agree with you, additionally, that intersubjectivity is not objectivity.