Divided Armies: Inequality and Battlefield Performance in Modern War

by Jason Lyall

How do armies fight and what makes them victorious on the modern battlefield? In Divided Armies, Jason Lyall challenges long-standing answers to this classic question by linking the fate of armies to their levels of inequality. Introducing the concept of military inequality, Lyall demonstrates how a state's prewar choices about the citizenship status of ethnic groups within its population determine subsequent battlefield performance. Treating certain ethnic groups as second-class citizens, either by subjecting them to state-sanctioned discrimination or, worse, violence, undermines interethnic trust, fuels grievances, and leads victimized soldiers to subvert military authorities once war begins. The higher an army's inequality, Lyall finds, the greater its rates of desertion, side-switching, casualties, and use of coercion to force soldiers to fight.

In a sweeping historical investigation, Lyall draws on Project Mars, a new dataset of 250 conventional wars fought since 1800, to test this argument. Project Mars breaks with prior efforts by including overlooked non-Western wars while cataloguing new patterns of inequality and wartime conduct across hundreds of belligerents. Combining historical comparisons and statistical analysis, Lyall also marshals evidence from nine wars, ranging from the Eastern Fronts of World War I and II to less familiar wars in Africa and Central Asia, to illustrate inequality's effects.

Sounding the alarm on the dangers of inequality for battlefield performance, Divided Armies offers important lessons about warfare over the past two centuries--and for wars still to come.

Genres: History, Nonfiction, Politics, Military History, War, Political Science, International Relations

528 pages, Paperback

Published February 11, 2020

About the author

Jason Lyall is the James Wright Chair of Transnational Studies at Dartmouth College.

Reviews

[Cyrus Samii · Rating 5 out of 5]

A methodological and substantive tour de force. Lyall uses a variety of methods to demonstrate how societal inequalities infiltrate military organization and undermine military effectiveness and cohesion.

The rigor here sets a new standard for military analysis, harkening back to classic military sociology like Shils and Janowitz, and making most commonly-referenced contemporary military experts (Biddle, Kagan, etc.) look like unschooled hacks.

[Spencer Willardson · Rating 4 out of 5]

This is a book I read mostly out of professional interest, but something that sits outside my direct research interests. I have a lot of thoughts about it, but will probably blog about it on my own blog in the coming weeks as I digest the arguments. It is an interesting book for those that are interested in military history or military effectiveness. It has a good mix of theory and empirical evidence and a mix of quantitative and narrative evidence as part of the empirics .

It is an impressive piece of research.