Why do people vote against their own interests?

I found this article very interesting.

The first thing that struck me is its detached tone -- sort of like the curious look a child gives when looking inside a cage at an exotic animal. Probably this was written by someone who lives in Great Brittain, looking over the Atlantic ocean with mild curiosity at how crazy the US health care situation is.

The second thing that struck me is that the observation is very true. A huge majority of the population in this country would benefit from health care reform, including the public option. Those who cannot afford health insurance now, those with pre-existing conditions, etc.

Yet, many people who stand to benefit angrily fight reform. It's just plain weird. Here are two quotes from the article:

• Why are so many American voters enraged by attempts to change a horribly inefficient system that leaves them with premiums they often cannot afford?
  
  
• In Texas, where barely two-thirds of the population have full health insurance and over a fifth of all children have no cover at all, opposition to the legislation is currently running at 87%.

Finally, the two books referenced by the article certainly look relevant, roughly concluding that the average American doesn't really make decisions based on facts. (This also means "trial by a jury of your peers" is not a very comforting approach.) While I haven't read these books, I have come to the same depressing conclusion.

A democracy is only as effective as its population is at making rational decisions.