This is something I have learned the last few years having to help moderate public forums, and the blogging community is now learning it after having their blogs filled with flame wars in the comments. Kathy Sierra explains how the oft-used claim that moderating forums is just a tool to create a fake world of happy people, implying, of course, that happy people are bad (ironic, eh?):

The notion of "Happy People" was tossed around in the Robert-Lost-His-Mind posts as something ridiculous at best, dangerous at worst. One blogger equated "happy people" with "vacuous". The idea seems to be that "happy people" implies those who are oblivious to the realities of life, in a fantasy of their own creation, and without the ability to think critically. The science, however, suggests just the opposite.
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_Happines_ is associated most heavily with the _left_ (i.e. logical) side of the brain, while _anger_ is associated with the _right_ (emotional, non-logical) side of the brain.

Obviously, it’s the angry people that are the problem, not the happy, i.e., rational, people.

And there's this one we hear most often, especially in reference to comment moderation--"if you can't say whatever the hell you want to express your anger, you can't be authentic and honest." While that may be true, here's what the psychologists say: _"Psychologists now say that this is a dangerous myth. Some people use this theory as a license to hurt others. Research has found that "letting it rip" with anger actually escalates anger and aggression and does nothing to help you (or the person you're angry with) resolve the situation._ _It's best to find out what it is that triggers your anger, and then to develop strategies to keep those triggers from tipping you over the edge."_

This is what we used to see all the time on our site. They defend it as “tough love” or “tellin’ it like it is, you just can’t deal”. They seem to believe it is their duty to mercilessly hurt others, as if that helps them or their cause. It’s sad, but those people will always be unhappy. The best thing to do is make them find another place to be unhappy and angry.