For the past two decades, scholars and policymakers have examined the phenomenon of China’s missing females and corresponding numbers of involuntary bachelors to better understand the causes and consequences of the state’s demographic plight. China has both a heavily skewed male to female sex ratio and faces a drastically shrinking population in coming years.

The emerging subfield of “security demographics” is interested in how demographic trends, such as youth bulges, high or low fertility rates, and sex ratios affect the security and stability of nation-states and regions. In our research, Andrea Den Boer and I have attempted to show that abnormally high sex ratios – situations where there are significantly more men than women – have been a security concern in the past and may affect security and stability in the future.