I know whereof you speak K, and after my initial flare of anger over their derision and mockery, I just find the whole thing (the groups, the "attack pack" who cruise larger forums like Religion and Health, the attitudes, the personalities, the focus on hating others) immensely sad.
Fear underlies it all--fear of not having all the answers, fear that what they've believed in all their lives might not be the whole truth, fear of being (omg omg omg) WRONG. They desire control in all aspect of their lives, and when they don't have it (imagine, someone out there might think differently!) they lash out and try to control them, when instead they should be trying to figure out why someone else's differing opinion bothers them so much.
It is very ironic that members of DU (these people in question included) pride themselves on being open-minded and tolerant liberals. I don't think these folks would like anyone to point out that they have more in common with the conservatives they hate so very much than they'd like to admit! 
What also makes me sad is that certain groups hang together on the slimmest of premises--hatred of others. I'm glad our little corner of the world is more supportive.
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