He doesn't have the power to delete threads or ban members because he doesn't like what they say - they need to break rules. I'd be very uneasy about imposing my personal opinion on the whole forum and I'm sure any mod feels the same.
Whenever such threads pop up I don't really see it as one sided - there are extreme opinions on both sides and a whole lot inbetween.
The depressing thing for me is no-one ever learns anything, they are unable to adjust their opinions so it's all a little bit pointless. Like this thread