Bruce Schneier’s argument that we prefer the feeling of security to security itself rests on a handful of mental mistakes that he thinks human beings make when they try to evaluate what’s risky and what’s safe. They include:

1) “We tend to exaggerate spectacular and rare risks and downplay common risks. So, flying versus driving.”

2) “The unknown is perceived to be riskier than the familiar. One example would be people fear kidnapping by strangers, when the data supports kidnapping by relatives is much more common.”

3) “Personified risks are perceived to be greater than anonymous risk. So Bin Laden is scarier because he has a name.”

4) “People underestimate risks in situations they do control and overestimate them in situations they don’t control. So once you take up skydiving or smoking, you downplay the risks. If a risk is thrust upon you — terrorism was a good example — you’ll overplay it, because you don’t feel like it’s in your control.”

5) “What newspapers do is they repeat again and again rare risks. I tell people, if it’s in the news, don’t worry about it. Because, by definition, news is something that almost never happens. When something is so common, it’s no longer news — car crashes, domestic violence — those are the risks you worry about.”

These misjudgments are particularly dangerous to policymaking because the rarity of these events undermines accountability. People may have dumb ideas about the economy, but they ultimately vote based on how the economy is doing, and so politicians know that their survival rests on effective management of the economy. Not so for extremely rare events.

If Congress does a bad job fortifying our ports against terrorist attack, there still might never be a successful attack on our ports. And if there is a successful attack, it likely won’t happen for years, at which point it’ll be another Congress’s problem. So if voters are demanding you make them feel safe now and you’re not likely to be around for, or connected to, the consequences of ignoring risks that no one is thinking about, it’s pretty natural to focus on the dangers your constituents want addressed rather than the dangers that actually need to be addressed.