The Economist: The link between polygamy and war. “Plural marriage, bred of inequality, begets violence.” (December 19, 2017)

“Wherever it is widely practised, polygamy (specifically polygyny, the taking of multiple wives) destabilises society, largely because it is a form of inequality which creates an urgent distress in the hearts, and loins, of young men. If a rich man has a Lamborghini, that does not mean that a poor man has to walk, for the supply of cars is not fixed. By contrast, every time a rich man takes an extra wife, another poor man must remain single. If the richest and most powerful 10% of men have, say, four wives each, the bottom 30% of men cannot marry. Young men will take desperate measures to avoid this state.

This is one of the reasons why the Arab Spring erupted, why the jihadists of Boko Haram and Islamic State were able to conquer swathes of Nigeria, Iraq and Syria, and why the polygamous parts of Indonesia and Haiti are so turbulent. Polygamous societies are bloodier, more likely to invade their neighbours and more prone to collapse than others are. The taking of multiple wives is a feature of life in all of the 20 most unstable countries on the Fragile States Index compiled by the Fund for Peace, an NGO”.