I think that as long as they do not violate the rules, they should not be banned.
The purpose of this forum is to get people to debate.
If people come on the forum insulting or threatening or using obscenities, then they should be banned. But if people - even evil people - come here to debate without insults or dirty language, they should be permitted to continue.
Of course, we don't want people to distract us from our main issues with fruitless and endless debates. The way to solve that problem is to lock threads that have exhausted their usefulness.
But I think banning should only be used when the rules are broken, and the latest black posters - while irritating - have not broken any rules in my opinion.
We are not afraid of debate and I think we handle ourselves very well.