I have pondered the psychology of politics for many years. I first concluded that fear was the defining difference: conservatives carry guns, live in gated communities, want controlled borders, support law and order and drive SUVs that feel safer. But liberals must have their own set of fears, which I saw as complementary: fear of separation, isolation, loss of community.
With this, I have come to see the issue as the boundary between self and other; conservatives want a strong barrier for two reasons: to prevent contamination from outside, and because weakening the dividing line blurs the distinction between self and other, leading to the loss of the ego and the dissolution of self.
The metaphor here is an amoeba, whose very existence depends on its cell membrane: no membrane, no amoeba. But stronger isn’t always better; it is necessary for the membrane to be permeable: nutrients must enter, and waste products must leave.
An op-ed in yesterday’s NYTimes describing experiments showing that bad smells or a dirty environment cause more conservative responses fits right in with the boundary hypothesis.
So where is the boundary to be drawn? Look at the idea of self. It is what we identify with; most obviously, our body, but also with our family, our town, our country, our friends, our career, our hobbies and our species, and we experience this through empathy(*) and feeling a part of something larger.
Is this bad? I think not; it gives us a sense of our place on the world, and I agree with Greta that this is the ethical direction to go in.
(*) Let me remind you how empathy became a dirty word to conservatives when Sotomayor was nominated for the Supreme Court.
UPDATE: A much more comprehensive and impressive article on What makes People Vote Rpublican? by Jonathan Haidt discusses 5 basic moral principles and how conservatives embrace all five, but liberals only two. Very thought-provoking.