It's easier to write criticism and insults than to write credible praise or do the work to engage and consider an argument.
I know of a band whose music is really beautiful and essentially non-political, yet they've actually had to suspend message board use on several occasions because it gets too heated.
I don't like it here when people resort to barbed sarcasm and insults (even though I've done it myself), and for the most part we can appeal to people's better nature here. Explaining that chest-beating and point scoring doesn't actually make anyone agree with you - quite the opposite - makes someone choose which one they'd rather have and 99 time out of a hundred folks here do re-engage. No matter what their opinion pretty much everyone who's ever posted here has reasons for their position and is smart enough to express them intelligently, and wants that position to be considered.
I do think we should pick one another up in a friendly and respectful way on inflammatory things as they start - this thread, which is by no means the worst ever, shows what happens when we don't.