Cognitive Bias and War

Why Hawks Win
by Daniel Kahneman and Jonathan Renshon (in Foreign Policy):

Excessive optimism is one of the most significant biases that psychologists have identified. Psychological research has shown that a large majority of people believe themselves to be smarter, more attractive, and more talented than average, and they commonly overestimate their future success. People are also prone to an “illusion of control”: They consistently exaggerate the amount of control they have over outcomes that are important to them—even when the outcomes are in fact random or determined by other forces. It is not difficult to see that this error may have led American policymakers astray as they laid the groundwork for the ongoing war in Iraq.
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It is apparent that hawks often have the upper hand as decision makers wrestle with questions of war and peace. And those advantages do not disappear as soon as the first bullets have flown. As the strategic calculus shifts to territory won or lost and casualties suffered, a new idiosyncrasy in human decision making appears: our deep-seated aversion to cutting our losses. Imagine, for example, the choice between:

Option A: A sure loss of $890

Option B: A 90 percent chance to lose $1,000 and a 10 percent chance to lose nothing.

In this situation, a large majority of decision makers will prefer the gamble in Option B, even though the other choice is statistically superior. People prefer to avoid a certain loss in favor of a potential loss, even if they risk losing significantly more. When things are going badly in a conflict, the aversion to cutting one’s losses, often compounded by wishful thinking, is likely to dominate the calculus of the losing side. This brew of psychological factors tends to cause conflicts to endure long beyond the point where a reasonable observer would see the outcome as a near certainty. Many other factors pull in the same direction, notably the fact that for the leaders who have led their nation to the brink of defeat, the consequences of giving up will usually not be worse if the conflict is prolonged, even if they are worse for the citizens they lead.

[AF]