What do you think?
Rate this book
War and Power
'Phillips Payson O'Brien is one of our finest historical thinkers.' James Holland, author of Normandy '44
War and power are two of the most-widely discussed issues in all of human history, and yet they are, time and again, misunderstood — often disastrously so.
Whilst we might think the outcome of war is determined by so-called ‘Great Powers’ who dominate their opponents with their impressive size and military prowess, the reality of modern conflict, as renowned strategic historian Professor Phillips Payson O’Brien demonstrates, is very different. He urges us instead to look for ‘Full Spectrum Powers’.
For if we are considering how powerful a nation is and who will win a war, we need to think less about weapons, and more about the economies and societies that produce them; less about individual battles, and more about sustaining campaigns and alliances in which states operate.
Using fascinating examples from the late 19th century to the present day, War and Power explains how misunderstanding war and power has led to terrible, even preventable conflicts – such as the war in Ukraine – and how more accurate analysis can help us consider the potential conflict between the US and China.
War and Power provides a bold new way of understanding the dangerous world around us.
War and power are two of the most-widely discussed issues in all of human history, and yet they are, time and again, misunderstood — often disastrously so.
Whilst we might think the outcome of war is determined by so-called ‘Great Powers’ who dominate their opponents with their impressive size and military prowess, the reality of modern conflict, as renowned strategic historian Professor Phillips Payson O’Brien demonstrates, is very different. He urges us instead to look for ‘Full Spectrum Powers’.
For if we are considering how powerful a nation is and who will win a war, we need to think less about weapons, and more about the economies and societies that produce them; less about individual battles, and more about sustaining campaigns and alliances in which states operate.
Using fascinating examples from the late 19th century to the present day, War and Power explains how misunderstanding war and power has led to terrible, even preventable conflicts – such as the war in Ukraine – and how more accurate analysis can help us consider the potential conflict between the US and China.
War and Power provides a bold new way of understanding the dangerous world around us.
368 pages, Hardcover
First published August 28, 2025
55 people are currently reading
535 people want to read
About the author
Phillips Payson O'Brien
11 books88 followersPhillips Payson O’Brien is a Professor of Strategic Studies at the University of St. Andrews in Fife, Scotland, where he has taught since 2016. A graduate of Trinity College in Hartford, Connecticut, O'Brien earned a PhD in British and American politics and naval policy before being selected as Cambridge University’s Mellon Research Fellow in American History, and a Drapers Research Fellow at Pembroke College.
Ratings & Reviews
Friends & Following
Create a free account to discover what your friends think of this book!
Community Reviews
Displaying 1 - 6 of 6 reviews
October 15, 2025
Key takeaways from this reading:
*Historically, economic power and technological development has trumped the physical size of a state and population. GDP and the purchasing power per capita of a nation can vastly guide war outcomes, which makes sense because a population that's starving isn't going to be at peak performance at the battlefront or at home. The relative resource abundance experienced by Germans in Nazi Germany at the start of WW2 compared to the rest of Europe backs this point.
*Short, decisive wars are a myth. Wars end when either side (and their allies) run out of resources and the battles need to stop so they can recoup. Individual battles cannot determine the outcomes of wars, but rather a complex interplay of a nation's morale, diplomacy and material resources (economic power that can directly be translated to military technology that can be fabricated, adapted and scaled up in production volume if necessary) can help explain outcomes.
*ALLIES matter a lot. Wars are rarely won by single entities acting alone, and rather, coalitions that can compile their resources and work together for a joint end-goal usually can persist through the end of the war. The author not only emphasizes the importance of execution of complex operations and machinery, but also the ability to recover+ maintain morale in a continual cycle and the multifaceted human element of war.
The language in this book was accessible to the average reader, but the organization of the arguments the author made was hard to follow. I felt like I was jumping around from subject to subject or between time periods (yes, warning this is not organized chronologically) and geographically (heavy focus on Europe, US and east Asia war history). The end goal is to relate how this new understanding of economic and technological power relates to the Russian occupation of Ukraine.
*Historically, economic power and technological development has trumped the physical size of a state and population. GDP and the purchasing power per capita of a nation can vastly guide war outcomes, which makes sense because a population that's starving isn't going to be at peak performance at the battlefront or at home. The relative resource abundance experienced by Germans in Nazi Germany at the start of WW2 compared to the rest of Europe backs this point.
*Short, decisive wars are a myth. Wars end when either side (and their allies) run out of resources and the battles need to stop so they can recoup. Individual battles cannot determine the outcomes of wars, but rather a complex interplay of a nation's morale, diplomacy and material resources (economic power that can directly be translated to military technology that can be fabricated, adapted and scaled up in production volume if necessary) can help explain outcomes.
*ALLIES matter a lot. Wars are rarely won by single entities acting alone, and rather, coalitions that can compile their resources and work together for a joint end-goal usually can persist through the end of the war. The author not only emphasizes the importance of execution of complex operations and machinery, but also the ability to recover+ maintain morale in a continual cycle and the multifaceted human element of war.
The language in this book was accessible to the average reader, but the organization of the arguments the author made was hard to follow. I felt like I was jumping around from subject to subject or between time periods (yes, warning this is not organized chronologically) and geographically (heavy focus on Europe, US and east Asia war history). The end goal is to relate how this new understanding of economic and technological power relates to the Russian occupation of Ukraine.
December 24, 2025
The prevailing model used by political theorists for understanding international relations is a theory of behaviour called neo-realism: the idea that states act as coherent entities (you can talk about "America" or "Iraq" doing things) and pursue a self-interested path to maximise their relative power over time (not only are "America" and "Iraq" agents in the world, they're cleverly doing what's best for them all the time).
If this sounds an awful lot like the basic assumptions of and fundamental problems with the study of economics and output of economists, you're on the right track.
It's a truism among historians that, for precisely the reasons listed above among others, the output of political theorists is worth markedly less than the paper it's printed on. The technical term—I believe originally from engineering—is "worse than useless". This is for reasons that are self-evident and bone-deep among historians but perhaps not immediately obvious to normal people and clearly not obvious to the political theorists, who—despite having a worse predictive-success ratio than a chimpanzee playing darts—continue busily producing their nonsense assessments and spouting their absurd analyses.
A notable example is that in the lead-up to February 2022 the only people correctly predicting that Ukraine would resist Putin and resist effectively were not political theorists (Foreign Affairs, probably the peak outlet of the political theory establishment at large, predicted a war over in weeks) or defence specialists (General Mark Milley, the most senior officer in the US armed services and principal military advisor to the president, predicted a war over in hours if not minutes), but historians.
O'Brien bridges the gap brilliantly, arguing simultaneously that a focus on extant military assets ("how many tanks have they got?") the constant preoccupation of military professionals, and that a belief in rational independent actors ("what maximises their relative advantage?"), the simplistic focus of political theorists, blinds both to the actual dynamics of power and conflict between states. He grounds his argument in several historical examples, showing how the tools used by political theorists and defence analysts could not predict either the course or the outcomes of the First World War, Second World War, Vietnam War, the Soviet invasion of Afghanistan, or indeed the present war in Ukraine.
It's not exactly gripping reading, but O'Brien's prose is lucid and fast-moving. It's a rare pleasure to see an entire discipline and structure of theory and received wisdom dismantled so unequivocally in such a brief and comprehensive way. In its place, O'Brien posits a tiered theory of mass, structure and leadership that aligns closely with the nuanced and interwoven way historians traditionally come at interpreting the past. Unfortunately, the people who'd need to buy this new theory in order for it to have an operative impact are the same people who seem satisfied with the terrible predictive power of their current analytical tools (Mark Milley kept his job for well over a year after his disastrous policy guidance on Ukraine, for instance); it seems unlikely to have much impact.
If this sounds an awful lot like the basic assumptions of and fundamental problems with the study of economics and output of economists, you're on the right track.
It's a truism among historians that, for precisely the reasons listed above among others, the output of political theorists is worth markedly less than the paper it's printed on. The technical term—I believe originally from engineering—is "worse than useless". This is for reasons that are self-evident and bone-deep among historians but perhaps not immediately obvious to normal people and clearly not obvious to the political theorists, who—despite having a worse predictive-success ratio than a chimpanzee playing darts—continue busily producing their nonsense assessments and spouting their absurd analyses.
A notable example is that in the lead-up to February 2022 the only people correctly predicting that Ukraine would resist Putin and resist effectively were not political theorists (Foreign Affairs, probably the peak outlet of the political theory establishment at large, predicted a war over in weeks) or defence specialists (General Mark Milley, the most senior officer in the US armed services and principal military advisor to the president, predicted a war over in hours if not minutes), but historians.
O'Brien bridges the gap brilliantly, arguing simultaneously that a focus on extant military assets ("how many tanks have they got?") the constant preoccupation of military professionals, and that a belief in rational independent actors ("what maximises their relative advantage?"), the simplistic focus of political theorists, blinds both to the actual dynamics of power and conflict between states. He grounds his argument in several historical examples, showing how the tools used by political theorists and defence analysts could not predict either the course or the outcomes of the First World War, Second World War, Vietnam War, the Soviet invasion of Afghanistan, or indeed the present war in Ukraine.
It's not exactly gripping reading, but O'Brien's prose is lucid and fast-moving. It's a rare pleasure to see an entire discipline and structure of theory and received wisdom dismantled so unequivocally in such a brief and comprehensive way. In its place, O'Brien posits a tiered theory of mass, structure and leadership that aligns closely with the nuanced and interwoven way historians traditionally come at interpreting the past. Unfortunately, the people who'd need to buy this new theory in order for it to have an operative impact are the same people who seem satisfied with the terrible predictive power of their current analytical tools (Mark Milley kept his job for well over a year after his disastrous policy guidance on Ukraine, for instance); it seems unlikely to have much impact.
September 20, 2025
Extremely interesting review of war and 'great powers' through, mostly the last two centuries. A much needed rehearsal that puts into context the successes and failures of the presumed hegemonic powers. And the clear impact of stupidity/ability in leaders and the lack of prediction capabilities by most of the military and political establishment to predict or even adapt to recent events such as the Ukraine-Russia war make a very worriesome prospect for the near future.
October 28, 2025
offers a provocative reevaluation of war, arguing that leadership, society, and alliances often matter more than sheer military might. It is challenging to follow in some places, but the inclusion of historical examples and timely relevance makes it worth reading.
November 23, 2025
An excellent follow-up to the author's work on WWII. Takes the lessons from that conflict about the key importance of force regeneration and generalises them effectively. Of particular importance to any realistic analysis of the power in our present day world.
December 14, 2025
Too much jumping from a subject to another. Also, what is the deal with em dashes? Felt like AI written content.
Displaying 1 - 6 of 6 reviews