Ed Glaeser writes; “Cities aren’t just places of economic productivity and cultural innovation. For millennia, they have also been the epicenters of dramatic political upheaval.” Glaeser’s piece is vague about what caused the initial uprising.
I can think of one big salient counter-example to his core urban density facilitating social contagion story. Leading development scholars have worried about the costs of Civil War in sub-Saharan Africa. One well known 2009 PNAS paper argued that climate change will raise deaths in this region by over 300,000 by 2030. These scholars claim that the probability of civil war is higher when average temperatures are higher. While they do not discuss “urbanization” in their piece, the only causal logic I can think of is that higher temperatures affect agricultural yields and that “Mad Max” from Thunderdome scarcity issues arise and this sparks violence. The PNAS paper appeas to conflict with Glaeser’s density point. In the case of Sub-Saharan Africa, I wonder if Civil War risk would decline as urbanization accelerates. Why? Fewer people would rely on subsistence agriculture for their incomes. Globalized free trade will provide the food for their cities. If civil war interests you, and you believe that economists have “value-added”, then read this!