On an individual level, the connection between age and violence is seemingly obvious. The fact that young people are more violent than their older fellow citizens is not only confirmed by crime statistics but is also suggested by studies from the fields of sociology and psychology. It is also noticeable that the proportion of young people – most of whom are men – is disproportionately high in violent uprisings, rebel groups, drug cartels, or terrorist groups. Young people are particularly susceptible to politically or religiously extreme ideologies on a developmental psychology level. In addition to this, young people are less incorporated into society through work or social ties such as marriage and family. Economists would therefore say that, for young people, joining a violent organization is associated with lower opportunity costs.

But can these observations really be so readily applied to a higher level? Or, put differently: Are countries with a particularly high proportion of young people automatically more vulnerable to uprisings and civil wars? This is the conclusion of a thesis called “Youth Bulge”, the name alluding to the bulging of age pyramids in populations with lots of young people. A radical exponent of the theory, the controversial German genocide researcher Gunnar Heinsohn sees a direct causal connection between the proportion of young men in a society and conflicts. His argument is that the number of promising social positions is insufficient when families have as many as three or four sons. Thus, it is not poverty that drives conflicts, but rather demographics and a lack of prospects: “People beg for bread, people shoot for social positions,” Heinsohn was once quoted as saying in a newspaper interview.

Few go as far as Heinsohn and declare the proportion of young men to be the main cause of conflict. And yet the Youth Bulge theory has seeped through into mainstream thought: In a report on armed violence published in 2011, for example, the OECD wrote that this violence was increasing due to “increasing youth populations without prospects”, among other things. Last but not least, during the “Arab Spring” in 2011, the high proportion of young people was often cited as an explanation for the uprisings. Daniel LaGraffe, for example, writes that demographic factors in the region have “played an important role in the widespread instability”.

Many questions nevertheless remain unanswered, especially with regard to methodology. The birth rate is directly related to other factors such as poverty or education. To say the least, this makes it difficult to form an independent variable to explain conflicts from the age structure. To cite the demographic increase as the main explanation for conflicts is also problematic because it cannot explain why, out of two countries with similar age structures, one is spared from conflict and the other not.

According to a recent study by Hannes Weber, having a large proportion of young people in a population does not automatically lead to instability or conflict. Under certain circumstances, however, an age structure like this is actually problematic. This is specifically the case when secondary and tertiary education in the population is expanded and the national economy stagnates at the same time. In this case, the labor market is not able to absorb the school and university graduates. Better education therefore leads to increased demands which, left unfilled, can lead to dissatisfaction and ultimately aggression. In any other environment, however, a high proportion of young people can be conducive to business and peace. We are then speaking of a “demographic dividend”.

However, the various studies on the impact of age structures on the risk of conflict also show that there is no consensus whatsoever. Whether a statistically relevant effect can be proven often depends on the specification of the model and the control variables included. This does not suggest that the theory is robust and requires a more detailed scientific investigation of the phenomenon at the very least.