As your token righty I'll take this one (actually libertarian, but close enough).
I think the post that said misunderstanding is a two way street was spot on. The anarchist undoubtedly sees Bush supporters as "not cool" because he's a friggin anarchist. Working for the Democratic campaign he would also find people more serious than those he meets at protests marches (because everyone shy of a revolutionary is more serious and less "cool" than him).
Likewise "Intellectual" is usually shorthand for "disagrees with me." People weight the facts differently (your 1.0 is my 0.0). Everyone has a set of issues where their position is "simple" (zero out most of the facts) where the other side considers it "complex" (lots of weighted facts). If you think "simple" only applies to the right then you haven't seen the dozens of different causes represented at protest marches whos supporters are frothing at the mouth
about Palestine, outsourcing, or corporations (saintly, evil, evil respectively).
Second - as any good ping pong player will tell you - you move to the place based on maximizing "can I play the ball there?" and "will the ball go there?"
You have limited possibilities of action so you pick the best one available. (okay, that was a long analogy). People and nations do this too, but since it
isn't ping pong people feel the need to defend their choice. Much of the anti-Americanism in my opinion comes from the fact that the US has a wider variety of choices than other countries. Friction happens when another country defends their position on moral grounds when really they made a choice on practical grounds (here is my list of possibilities, pick the best one). This causes friction because to be consistent you then have to bash the other guy as unmoral. This works for individuals too, there are only some possibile positions you can take that are consistent with your beliefs. The other guy has a different set of possibilities and when they don't overlap you get friction.
NB, I tried hard to say little inflamatory. If you think this was flamebait you don't read the internet much ;)