[P]artisans reject facts because they produce cognitive dissonance — the psychological experience of having to hold inconsistent ideas in one’s head. When Democrats hear the argument that the president can do something about high gas prices, that produces dissonance because it clashes with the loyalties these voters feel toward Obama. The same thing happens when Republicans hear that Obama cannot be held responsible for high gas prices — the information challenges their dislike of the president.
I think this phenomenon explains a lot of political attitudes in America. It also helps explain why so many people get frustrated with politics.