After 9/11, Al Gore called together a number of scientists who might be able to help him understand "why they hate us?" Generally, scholars believe that terrorism is driven by collective humiliation, a sense of disrespect, and existential desires to defend one's way of life. One scholar, however, presented a dramatically different perspective.
When Rose McDermott's advisor Richard Wrangham was asked "Why do they hate us?" He responded: "Polygamy... specifically polygyny." (Polygyny is a form of polygamy where one man has many wives.)
To support this argument in her presentation at the Stanford Summer Institute in Political Psychology, McDermott presented an immense quantity of correlational data. She showed correlations between the proportion of single males to females in a society (which is high in polygynous countries as many women are monopolized by a a few men, leaving many men single) and the rate of violent crimes against women, gang membership, and support for aggressive militarism, presumably all in pursuit of finding women to pass one's genes onto subsequent generations. Further, she shows relationships between polygyny and proportions of terrorists coming from those countries. Ergo, polygyny causes terrorism and causes polygynous countries, like many of those in the Middle East to hate the United States, right?
Not so fast, my friends. (* this is my personal opinion; not Rose McDermott's; I find this argument to be unconvincing *)
Correlation does not imply causation. It may be unfeasible to experimentally manipulate the legality and prevalence of polygyny in different cultures, but there are ways to strengthen a claim. When claims are as radical as this one, it is especially important to stand on firm empirical ground. In order to claim that polygyny causes terrorism, it'd be useful to conduct cross-cultural, cross-historical analyses and test whether societies become less violent as the prevalence of polygyny decreases. The converse should also be tested; do societies also become more violent as the prevalence of polygyny increases?
This all assumes that the factor driving violence is polygyny, but that is a big assumption. Polygyny tends to be higher in non-western, poorer, more religious, and less educated societies. In order to defend the claim that polygyny is the driving factor, these variables should be assessed in tandem with the prevalence of polygyny; they should not simply be "statistically controlled for." Much research (for example, see Rothschild's research) shows that religious fundamentalism drives support for violent action against other cultures. Other work suggests that perhaps relative economic deprivation drives disorder and increased rates of violence (for example, see Broken Windows Theory, and some of my own research). If religious belief and these other factors lead to differing rates of polygyny, then a fundamental statistical assumption of these tests is violated and artificially distort the results, potentially rendering them meaningless (for fellow stats geeks, this violation is known as heterogeneity of regression slopes). If these variables were included in the model as factors, then we could get a better sense of the unique relationship between polygyny and violence.
Still. Even if these more comprehensive techniques were adopted, these data are correlational and incapable of demonstrating a causal relationship. Again, this is my critique, not hers. At the end of McDermott's lecture when I asked what we could do to reduce worldwide terrorism, her response was, "Ban polygyny."
She remarked that Al Gore sent letters of gratitude to 11 of the 12 attendees of the conference he organized following 9/11. The one person who did not get a letter of gratitude was Rose McDermott's advisor Richard Wrangham. Later in the week, I asked terrorism scholar Jerrold Post if Gore was wrong in not sending a letter of gratitude for Wrangham and McDermott's theory of terrorism. He shook his head and said he had "no knowledge of any link between sex and terrorism."
What do you think?