What's a little amateur psychoanalysis among friends? So here is my shot at it:
I believe the Western Left (or at least the vocal elements of it, on Internet mailing lists, etc) is what I like to call the MENSA left. Extremely bright people who arrived at their left positions not because of organized struggle, spiritual awakening or instruction, etc., but because they were bright enough to figure things out. But part of being smart is the desire to be the smartest, and hence the strife. There is also an element of righteousness to it, I think, since smartness leads to determinism, scientism, etc -- stuff that makes you believe not only in the one true way/thing/idea but also to believe that yours is it (unless proven wrong). The more parsimonious and fair explanation is probably that the left is bound to feel frustration and nastiness (especially internal) is a predictable outcome.
The right, being not that bright, naturally recognizes that its strength lies in numbers, and instinctively bonds organically and emphasizes such things as creating and sticking to a message, loyalty, etc, over "truth", "analysis", etc.
FWIW!!!
--ravi
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