How Militaries Change in Wartime
Oxford University Press, 2020, ISBN 9780197661703, 432 pp
Authors: David Barno and Nora Bensahel
Reviewed by: Rebecca Marlow
In Adaptation Under Fire: How militaries Change in Wartime, Lieutenant General David Barno USA (Ret.) and Dr. Nora Bensahel have collaborated to provide a systematic analysis of the factors that they believe contribute to a military’s ability to adapt in wartime and how those factors could be applied to a peacetime military. They have previously co-authored a number of articles for War on the Rocks covering a wide range of topics, including leadership and training, as well as a number of individual papers. Both authors are currently professors at Johns Hopkins School of Advanced International Studies.
Adaptation Under Fire is broken into three parts. In Part I, the authors define their understanding of adaptation versus innovation. Their position is that adaptation occurs when there is a lack of time but sufficient resources, while innovation occurs when there is ample time but a lack of resources. They then outline how they are assessing military adaptability for the purposes of this book through an analytic framework of doctrine, technology and leadership. To verify this framework, the authors first apply it to a range of examples of military adaptation during wars of the 20th century across multiple nations and conflicts, comparing successes and failures for each of their criteria. Doctrinal examples analysed include a comparison of German and French doctrine at the beginning of World War Two in 1939 and then Israeli and Egyptian doctrine during the Yom Kippur War in 1973. Barno and Bensahel emphasise the role of initiative (or lack thereof) versus the accuracy of the doctrine at the start of the conflict. Among these historical analyses, the authors compare four examples of tank adaptability, including that of the M4 ‘Sherman’ of World War Two, an incident that illustrates an institutional failure to adapt rather than a tactical adaption failure. Compared to the other chapters in Part I, this chapter on technology adaption is less cohesive and comprehensive, but nonetheless of significant interest.
Part II of Adaptation under Fire uses the same analytic framework of doctrine, technology and leadership introduced in Part I to understand US military adaptation during recent wars, particularly within the long Iraq and Afghanistan conflicts. The expertise of the authors in their analysis on the more recent conflicts is evident. Each chapter is a comparison of tactical and theatre level adaptation and, unlike Part I, not every analysis has an example of failure versus success. Part II champions the successes but is not afraid to be critical of the failures and why the attempts at adaptation failed in each case. Tactical and theatre level leadership come into strong focus, each having their own chapters. Barno and Bensahel make a point of noting the long reaching influence of the Vietnam War on US theatre level commanders. This meant that, unlike more junior officers, they struggled to adapt beyond post-Vietnam era thinking[1]
The third and final part brings the reader back to the central question of the book: is the US military sufficiently adaptable for the wars of the future? In three chapters, the authors explore the challenges of future war that they have discerned, provide an assessment of US military adaptability as of 2020, and identify ways in which adaptability could be improved. The authors discuss the importance for leaders to be adaptive in order to empower their subordinates’ adaptability; this need exists across doctrine, training and technology. It will require a deliberate approach to achieve diversity of thought instead of recourse to planning based on previous wars.[2] Linked to this theme, the authors have woven a thread through the chapter concerning the impact of bureaucracy that necessarily exists in all militaries and the preference for incremental change over wholesale change, even when that change is needed.
Adaptation has become a topic of increasing interest over the past 18 months within Army. In November 2024 Chief of Army, Lieutenant General Simon Stuart, declared that he was ‘not assured’ that Army would be able to ‘win the battle of adaptation in the face of a major war in our region’.[3] To this end, the Chief of Army Chauvel Prize topic of 2026 follows the theme of adaptation, questioning how the Army can be required to ‘continually adapt to the changing character of war’.[4] Adaptation under Fire helps add to the discussion Army is currently having. There are many relevant examples across multiple wars in which Army has adapted and moved forward. The imminent restructure of the Australian Defence Force’s (ADF) acquisition organisations may lead to Army having less ability to shape future technologies. Therefore Barno and Bensahel’s suggestion of a focus on educating leaders and writing adaptable doctrine are potentially the most applicable and beneficial paths available for Army to enhance its capacity for adaptation. The authors articulate that it is with strong leadership that deficiencies in technology and doctrine can be overcome, but weak leadership will not make up for any shortfalls in these areas.[5]
Broader than Army, the ADF continues to work through the re-design of our force. Adaptation Under Fire provides a considered framework that the ADF could apply to round out the mission engineering process which is assessing the force design. Thus the book is worth reading for those who are undertaking and overseeing this process. Such consideration is essential in order to ensure that the ADF future force is capable of adapting to the wars of the 21st Century. When planning our future force, applying the fundamentals identified by Barno and Bensahel (doctrine, technology and leadership) to all aspects of planning could help prevent an unnecessarily narrow focus on a single aspect of the force.
The Australian Army’s role in securing victory in a future conflict will require it to adapt to the changing context of conflict. As the authors remind us, “even though fighting in future wars will take place at sea and in the air, outer space, and cyber space, most will still be won or lost in battles to control the land and its people.”[6]
Endnotes
[1] David Barno and Nora Bensahel, Adaptation under Fire: How Militaries Change in Wartime (Oxford University Press, 2020), 228.
[2] David Barno and Nora Bensahel, Adaptation under Fire, 262.
[3] Simon Stuart, ‘The Challenges to the Australian Army Profession’, Presentation to the National Security College, Australian National University, Canberra, 25 November 2024, https://www.army.gov.au/news-and-events/speeches-and-transcripts/2024-1….
[4] ‘The Chief of Army Essay Competition and Chauvel Prize’, Australian Army Research Centre.
[5] Barno and Bensahel, Adaptation under Fire, 28.
[6] Barno and Bensahel, Adaptation under Fire, 5.
