The irrationality of American politics

Not exactly a state secret, but there's been a recent attempt to describe it more precisely. Money quote:

The world is a complex place. Most people are inevitably ignorant about most things, which is why shows like "Are You Smarter than a 5th Grader?" are funny... Many political scientists think this does not matter because of a phenomenon called the "miracle of aggregation" or, more poetically, the "wisdom of crowds". If ignorant voters vote randomly, the candidate who wins a majority of well-informed voters will win... Caplan says that politics is different because ignorant voters do not vote randomly.

Instead, he identifies four biases that prompt voters systematically to demand policies that make them worse off. First, people do not understand how the pursuit of private profits often yields public benefits: they have an anti-market bias. Second, they underestimate the benefits of interactions with foreigners: they have an anti-foreign bias. Third, they equate prosperity with employment rather than production: Mr Caplan calls this the "make-work bias". Finally, they tend to think economic conditions are worse than they are, a bias towards pessimism.