In most “risky” situations we encounter in everyday life — going for a walk, having sex with someone for the first time, playing baseball, etc. — the severity of the consequences are things that humans have been coping with for millions of years — twisting an ankle, getting pregnant, breaking an arm, etc. Risk factor (b) — the severity of the consequences — are things we can easily understand, so we can realistically assess the probability (risk factor (a)) and realistically calculate our overall risk level. Even somewhat more hazardous situations — driving to work on the freeway, installing a hydroelectric powerplant, building the Golden Gate bridge, taking an elevator to the top of a 100-story building, etc. — are still things that have analogies that we can easily relate to from our evolutionary past: riding a fast horse, installing a waterwheel to produce power, building an ox bridge, climbing a tree, etc. Falling out of a 100-story building won’t (broadly speaking) make you any more dead than if you fall out of a 20-foot tree.

However, things get much harder when we deal with problems that have extremely severe consequences — when analogies to past human experience don’t exist.

In the 20th-century, we began building nuclear powerplants, and we had a very hard time evaluating the risks. Why? Because even though the odds of something bad happening (risk factor (a)) were relatively low compared to other types of powerplants (hydroelectric, coal-fired, etc.), the severity of the potential consequences if something bad actually happened (risk factor (b)) was overwhelmingly beyond anything humans had ever dealt with before. Consequently, instead of assessing the risks in our usual way (multiplying the odds times the severity level of each risk), we as a society became obsessed with reducing the odds (risk factor (a)) to astronomically small levels. In essence, the severity of a bad outcome (a core meltdown followed by widespread radiation exposure…and possibly tens of thousands of fatalities) distorted our thinking, because the situation was unlike anything humans had ever encountered before.

Let’s now consider the 9/11 terrorist attack. Three thousand innocent people died that day and a lot of valuable property was destroyed, but much more happened that day. Images of jetliners flying into buildings, of people jumping to their deaths to avoid being burned alive, of landmark buildings collapsing onto the heroic people trapped inside, etc., were seared into the minds of every American. The result: an extreme example of a severe consequence (risk factor (b)) which then distorted our thinking in how we perceived the risk of another terrorist attack.

The reality is that the death of 3,000 people is something we ignore every single day. As I pointed out in the post Erich mentions, 3,000 people die annually of colon cancer in Wisconsin — every single year — and life goes on. Every year, 100,000 people die from human errors in hospitals — every single year — and life goes on. Every year, 60,000 people die from pneumonia — every single year — and life goes on. Every year, 400,000 people die from cigarettes — every single year — and life goes on. In the scheme of things, the 3,000 people who died on 9/11 are a DROP IN THE BUCKET compared to all the other things that kill Americans. The probability that an American will die from a terrorist attack is less than the probability that he or she will die from colon cancer in Wisconsin. Yet look at how our nation has reacted: hundreds of billions of dollars and tens of thousands of innocent lives (American, British, Iraqi, etc.) spent to invade a country that had nothing to do with the 9/11 attack.

Let me anticipate the neocon objection: what about the next terrorist attack that destroys a whole city? My answer: hurricane Katrina destroyed a whole city and life still goes on. Hurricanes Floyd, Andrew, Wilma, etc., destroyed whole cities and life still goes on. Hurricane Mitch changed the landscape of Honduras so much that entirely new maps of the country were needed, and life still goes on. The Great San Francisco Earthquake of 1906 destroyed a whole city and life still goes on. The 2004 tsunami destroyed dozens of cities across the globe and killed hundreds of thousands of people, and life still goes on. The nuclear bombs dropped on Hiroshima and Nagasaki destroyed entire cities, and life still goes on.

My point is not to trivialize the threat posed by terrorists — destroying two skyscrapers or blowing up ten jetliners in one day is obviously a very bad thing — but to suggest that terrorism is the greatest threat America faces and that it should be our nation’s top priority is, by any *objective* measure, completely ridiculous. Unfortunately, Americans have been so emotionally disturbed by the potential severity of a terrorist attack (risk factor (b)) that they have distorted their thinking about how to assess the threat. Of course, it’s not entirely their fault: the neocons have been feeding America a steady diet of lies and propaganda to exaggerate fear and foster paranoia about terrorism, because doing so directly benefits the neocon agenda.

The solution is for people to try harder to set aside their emotions and look more objectively at the actual threat posed by terrorists, relative to all the other threats and risks that each of us faces. When more Americans realize that they are far more likely to die in a car accident while driving to work, than to die from an international terrorist attack, they will go a long way toward dealing effectively with terrorism and avoiding gigantic mistakes such as the one in Iraq.