I mostly agree with how Mary said she would handle it.

The problem with the 'let them argue it out' argument is that unless there is a final resolution in the end, the process will continue in other threads anyway. If it is recognised by a moderator that this is not happening, they may need to step in and facilitate it. There is a point in any new relationship when people have a tendency to jockey for what the see as their place. This is normal. Some of what we have been witnessing and enduring is beyond that, it is pure and simple harassment, ridicule and trolling and needs to be addressed somehow.

Sometimes a moderator has to step in and make sure a resolution or agreement between the two parties occurs, otherwise it's fruitless to let people argue constantly. Moderators have to have some wisdom, that is what makes moderators like mattew and mmcarthy good at what they do. azz over at ubuntu was an excellent moderator, but mike (kiwi) put an end to that as he has made an enormous amount of bad calls there.

When I ran my forum, I had the attitude that I would deal with issues if and when they would arise. I never even really read the default set of rules that came with the software. When Utabintarbo showed up and asked if he could participate (he and I had had some aruments at ubuntu and he had recently been banned there), I said 'of course your welcome'. I set the tone right off the bat by making everyone feel like they belonged and I would treat them as adults. My forum did not last very long however, not because of what I just talked about but because I just did not want to put the effort into it. I learned some good lessons from it, and I found out who some people were and I learned to admire some of them.