A Philosopher's Blog

Threat Assessment I: A Vivid Spotlight

Posted in Ethics, Philosophy, Politics, Reasoning/Logic by Michael LaBossiere on December 16, 2015

When engaged in rational threat assessment, there are two main factors that need to be considered. The first is the probability of the threat. The second is, very broadly speaking, the severity of the threat. These two can be combined into one sweeping question: “how likely is it that this will happen and, if it does, how bad will it be?”

Making rational decisions about dangers involves considering both of these factors. For example, consider the risks of going to a crowded area such as a movie theater or school. There is a high probability of being exposed to the cold virus, but it is a very low severity threat. There is an exceedingly low probability that there will be a mass shooting, but it is a high severity threat since it can result in injury or death.

While humans have done a fairly good job at surviving, this seems to have been despite our amazingly bad skills at rational threat assessment. To be specific, the worry people feel in regards to a threat generally does not match up with the actual probability of the threat occurring. People do seem somewhat better at assessing the severity, though they are also often in error about this.

One excellent example of poor threat assessment is in regards to the fear Americans have in regards to domestic terrorism. As of December 15, 2015 there have been 45 people killed in the United States in attacks classified as “violent jihadist attacks” and 48 people killed in attacks classified as “far right wing attacks” since 9/11/2001.  In contrast, there were 301,797 gun deaths from 2005-2015 in the United States and over 30,000 people are killed each year in motor vehicle crashes in the United States.

Despite the incredibly low likelihood of a person being killed by an act of terrorism in the United States, many people are terrified by terrorism (which is, of course, the goal of terrorism) and have become rather focused on the matter since the murders in San Bernardino. Although there have been no acts of terrorism on the part of refugees in the United States, many people are terrified of refugees and this had led to calls for refusing to accept Syrian refugees and Donald Trump has famously called for a ban on all Muslims entering the United States.

Given that an American is vastly more likely to be killed while driving than killed by a terrorist, it might be wondered why people are so incredibly bad at this sort of threat assessment. The answer, in regards to having fear vastly out of proportion to the probability is easy enough—it involves a cognitive bias and some classic fallacies.

People follow general rules when they estimate probabilities and the ones we use unconsciously are called heuristics. While the right way to estimate probability is to use proper statistical methods, people generally fall victim to the bias known as the availability heuristic. The idea is that a person unconsciously assigns a probability to something based on how often they think of that sort of event. While an event that occurs often will tend to be thought of often, the fact that something is often thought of does not make it more likely to occur.

After an incident of domestic terrorism, people think about terrorism far more often and thus tend to unconsciously believe that the chance of terrorism occurring is far higher than it really is. To use a non-terrorist example, when people hear about a shark attack, they tend to think that the chances of it occurring are high—even though the probability is incredibly low (driving to the beach is vastly more likely to kill you than a shark is). The defense against this bias is to find reliable statistical data and use that as the basis for inferences about threats—that is, think it through rather than trying to feel through it. This is, of course, very difficult: people tend to regard their feelings, however unwarranted, as the best evidence—despite it is usually the worst evidence.

People are also misled about probability by various fallacies. One is the spotlight fallacy. The spotlight fallacy is committed when a person uncritically assumes that all (or many) members or cases of a certain class or type are like those that receive the most attention or coverage in the media. After an incident involving terrorists who are Muslim, media attention is focused on that fact, leading people who are poor at reasoning to infer that most Muslims are terrorists. This is the exact sort of mistake that would occur if it were inferred that most Christians are terrorists because the media covered a terrorist who was Christian (who shot up a Planned Parenthood). If people believe that, for example, most Muslims are terrorists, then they will make incorrect inferences about the probability of a domestic terrorist attack by Muslims.

Anecdotal evidence is another fallacy that contributes to poor inferences about the probability of a threat. This fallacy is committed when a person draws a conclusion about a population based on an anecdote (a story) about one or a very small number of cases. The fallacy is also committed when someone rejects reasonable statistical data supporting a claim in favor of a single example or small number of examples that go against the claim. This fallacy is similar to hasty generalization and a similar sort of error is committed, namely drawing an inference based on a sample that is inadequate in size relative to the conclusion. The main difference between hasty generalization and anecdotal evidence is that the fallacy anecdotal evidence involves using a story (anecdote) as the sample.

People often fall victim to this fallacy because stories and anecdotes tend to have more psychological influence than statistical data. This leads people to infer that what is true in an anecdote must be true of the whole population or that an anecdote justifies rejecting statistical evidence in favor of said anecdote. Not surprisingly, people most commonly accept this fallacy because they want to believe that what is true in the anecdote is true for the whole population.

In the case of terrorism, people use both anecdotal evidence and hasty generalization: they point to a few examples of domestic terrorism or tell the story about a specific incident, and then draw an unwarranted conclusion about the probability of a terrorist attack occurring. For example, people point to the claim that one of the terrorists in Paris masqueraded as a refugee and infer that refugees pose a great threat to the United States. Or they tell the story about the one attacker in San Bernardino who arrived in the states on a K-1 (“fiancé”) visa and make unwarranted conclusions about the danger of the visa system (which is used by about 25,000 people a year).

One last fallacy is misleading vividness. This occurs when a very small number of particularly dramatic events are taken to outweigh a significant amount of statistical evidence. This sort of “reasoning” is fallacious because the mere fact that an event is particularly vivid or dramatic does not make the event more likely to occur, especially in the face of significant statistical evidence to the contrary.

People often accept this sort of “reasoning” because particularly vivid or dramatic cases tend to make a very strong impression on the human mind. For example, mass shootings by domestic terrorists are vivid and awful, so it is hardly surprising that people feel they are very much in danger from such attacks. Another way to look at this fallacy in the context of threats is that a person conflates the severity of a threat with its probability. That is, the worse the harm, the more a person feels that it will occur.

It should be kept in mind that taking into account the possibility of something dramatic or vivid occurring is not always fallacious. For example, a person might decide to never go sky diving because the effects of an accident can be very, very dramatic. If he knows that, statistically, the chances of the accident are happening are very low but he considers even a small risk to be unacceptable, then he would not be making this error in reasoning. This then becomes a matter of value judgment—how much risk is a person willing to tolerate relative to the severity of the potential harm.

The defense against these fallacies is to use a proper statistical analysis as the basis for inferences about probability. As noted above, there is still the psychological problem: people tend to act on the basis on how they feel rather than what the facts show.

Such rational assessment of threats is rather important for both practical and moral reasons. The matter of terrorism is no exception to this.  Since society has limited resources, rationally using them requires considering the probability of threats rationally—otherwise resources are being misspent. For example, spending billions to counter a miniscule threat while spending little on leading causes of harm would be irrational (if the goal is to protect people from harm). There is also the concern about the harm of creating fear that is unfounded. In addition to the psychological harm to individuals, there is also the damage to the social fabric. There has already been an increase in attacks on Muslims in America and people are seriously considering abandoning core American values, such as the freedom of religion and being good Samaritans.

In light of the above, I urge people to think rather than feel their way through their concerns about terrorism. Also, I urge people to stop listening to Donald Trump. He has the right of free expression, but people also have the right of free listening.


My Amazon Author Page

My Paizo Page

My DriveThru RPG Page

Follow Me on Twitter


13 Responses

Subscribe to comments with RSS.

  1. TJB said, on December 16, 2015 at 8:52 am

    Mike, if you were in charge of the L.A. School district, would you have closed the schools based on a terror threat?

  2. ajmacdonaldjr said, on December 16, 2015 at 11:06 am

    • ronster12012 said, on December 16, 2015 at 12:24 pm


      What a stupid question, of curse Iraq was better off with Saddam Hussein, millions of dead Iraqis would say that too if they could.

  3. TJB said, on December 16, 2015 at 12:58 pm

    ronster is right. Given a choice between a secular dictatorship and an Islamic theocracy, I think the dictatorship is the lesser evil.

    • ronster12012 said, on December 16, 2015 at 9:05 pm


      For a bit more heresy lol, I don’t happen to think that democracy is the best possible system at all times and in all places. It is fairly obvious (from a purely practical, not ideological POV)that different societies have different needs.

      Africa is full of ‘democracies’ that are as corrupt and oppressive as any feudal monarchy yet Singapore was run as a virtual dictatorship for many years by Lee Kwan Yew….and look what it is now.

      Saddam went down for other reasons, economic and geopolitical, the dictator tag was just to sell us the war to remove him. Same again for Gaddafi and now Assad.

      this is not to say that all dictatorships are good,, of course. FWIW, I worked with a couple of Iraqis in the early 90’s, both of whom hated Saddam as they were Assyrian catholics, but they did say that if one kept out of politics Iraq in the 80’s was a really great place to live.The most developed country in the ME outside of Israel….perhaps that was its problem?

  4. TJB said, on December 16, 2015 at 5:22 pm

    Mike, do you really believe the danger from terrorism is really only at the 3-4 deaths per year level?

    Would it not be more honest to say that the danger is much greater than this, but due to a so far highly effective counter-terror program, the death count has been held relatively low?

    • ronster12012 said, on December 16, 2015 at 9:16 pm


      The threat is not from 3 or 4 deaths a year, which are inconsequential to all those not directly affected, but from a growing population of people who do not share your values.

      Threat assessment doesn’t just include current threats but reasonably foreseeable threats into the future. It isn’t rocket science to work out that 1/ populations tend to stay put geographically 2/ everyone wants to express their values and if they can’t become resentful then angry 3/ islam is an expansionist and totalitarian creed 4/ sooner or later those elements will collide with American values 5/ if moslems then persist then one has a civil war on one’s hands. 6/ it is not about individuals but groups. 6/ we are blinded by our own inclusionist worldview.

    • Michael LaBossiere said, on December 17, 2015 at 6:30 pm

      To calculate the risk, we would need to take into account the thwarted attempts–assessing the likelihood they would have occurred and the damage they would have done. Based on the available information, terrorism is a minuscule threat in the United States.

      While we do not have access to the secret information, if the NSA spying is any indication of how effective our efforts are, then the low death count is due to the low number of attempts. That is, the number of attacks is tiny.

      Now, it is worth considering the doomsday scenarios: what if a terrorist got a small nuke into NYC or a nasty biological weapon?

      • TJB said, on December 17, 2015 at 9:31 pm

        Mike, the rest of us are factoring this scenario into our thinking. Has this just occurred to you?

  5. nailheadtom said, on December 16, 2015 at 9:20 pm

    On a personal level, there’s practically no danger from a jihadi attack to any particular American in the US. Use of the word “terrorism” in this context is silly. Calling an event that is referred to as terrorism an “isolated jihadi attack” is more accurate.

    Aside from this, the danger to Americans from isolated jihadi attacks isn’t from the attacks themselves but instead is from the state’s reaction to such attacks. Even before the jihadis began their activities, the US government was expanding its surveillance over its own citizens, setting up sting operations, monitoring communications, recording transactions and other legal activities. The perception that jihadi attacks are becoming deadlier has only served to increase these moves. The reason that they’re dangerous to all Americans is that no one can guarantee that the records kept by the state will remain forever exclusively with the state. Believe it or not, all states eventually succumb to outside forces or are taken over by opponents within them. The new masters will be happy to have access to all the carefully collected information that even a benign state possesses, and even more so that stored away by a pathological bureaucracy intent on recording every aspect of the lives of its subjects. Various levels of government have a very dangerous amount of information about its subjects on file that would be put to use in the event that the national government were controlled by other, more efficient and tyrannical forces.

    • ronster12012 said, on December 16, 2015 at 9:35 pm


      Now that really is thinking 5 steps ahead!!! Pity is that most of us spend all our time getting through the week with busy lives and too many demands on us to think about next year or next decade or thirty years ahead but there are those out there that do….and they may not have our best interests at heart.

    • nailheadtom said, on December 17, 2015 at 7:07 pm

      A glimpse of the techniques used to discover isolated jihadis is given here by noted author William T. Vollmann: http://harpers.org/archive/2013/09/life-as-a-terrorist/

  6. Emilee Mcniel said, on December 17, 2016 at 11:57 pm

    notepad bluebox

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: