The strength of John Mearsheimer’s The Tragedy of Great Power Politics is also its inherent weakness.  This review will analyze the strengths of Mearsheimer’s approach to the argument, and will then explore where the argument appears to be lacking.  What Mearsheimer creates in this book is a carefully argued defense of offensive realism, and he does a very good job of defining his space within the broader realist school of thought.  In order to create a well-reasoned, logically cohesive argument, Mearsheimer has to focus on a relatively short time-frame, with what I found to be a problematically small sample of events.  While his analytic framework pointed out the consistency of offensive realism in state behavior from the late 18^th Century to the present, to claim that offensive realism as defined in the book is “predictive” of state behavior is highly problematic.  A final, critical, weakness to the book was that Mearsheimer’s historical case studies either all suffered massive collapse, or took non-offensive approaches to power projection; the most offensive examples didn’t survive long, and survivors at times behaved less offensively.  His logic for addressing non-military offensive behavior, particularly his economic analysis, struck me as antiquated and lacking a recognition of contemporary financial economics.

The strength of the book is in the argumentative design.  Mearsheimer does a very good job of laying out how he defines his cases, focusing on great powers within a modern timeframe.  His process for indexing wealth and population to define great power status provide the reader with a reliable objective marker for case study inclusion.  The effort he makes to define offensive realism relative to classical and defensive realism was also appreciated, and would be a good primer on realism and its variations for a reader lacking an in-depth background in realist thought.  By defining realism and what constitutes a case study, he was then able to logically put aside subjective aspects of political behavior and demonstrate that across cultural and socio-linguistic cases great powers behave in a way that offensive realism would predict.  The problems with the argument as a whole begin to come to light at this stage, since Mearsheimer is limited to a small sample size of cases, uses case studies that were not durable survivors, and uses an antiquated view of political economy when discussing future conflicts.

While the data in the book points quite equivocally to states behaving in offensive realist terms, the small sample size creates problems for the claim that offensive realism “predicts” particular state behavior.  Due to the structure of the argument and the method of analyzing cases, which was not statistical but historical, the claim of prediction is highly problematic.  Even within the context of Mearsheimer’s cases, there is significant uncertainty about when a war will start, and type-1 errors are quite common (for example, Wilhelmein Germany’s decision not to go to war in the 1900-1909 timeframe, when offensive realism predicted the highest likelihood of German aggression).  The field of conflict prediction is highly problematic generally, and compared to statistically significant indices of risk with much larger sample sizes[1], Mearsheimer’s claim that offensive realism predicts behavior seems lacking; at best it describes the already observed behavior a set of carefully defined cases.

Aside from methodology, there are two aspects of Mearsheimer’s argument that warrant further inspection.  Since offensive realism is defined as the best way to ensure state survival, it seems logically problematic that so many cases Mearsheimer cites were vanquished in wars.  Wilhelmein and Nazi Germany, after significant offensive expansion were left shattered by two World Wars, Napoleonic France was beaten at Waterloo, and the Soviet Union collapsed.  Offensive realism might have defined their behavior, but it does not seem to be a good survival strategy in the long run.  His economic analysis also seems overly simplistic.  In his historical examples economies were driven by manufacturing; the current global economy is driven by financial futures instruments.  In light of that, will China behave as offensively as possible if they know that the United States can put a “stop payment” order on treasury bonds and collapse their economy?  A war under those conditions would be very short-lived for China, and perhaps a liberalist like Steven van Evera’s work would be a better place to look when trying to understand where U.S. – China relations are going from a economic power perspective.

Mearsheimer has produced a book that very effectively lays out the calculus of great power behavior within an offensive paradigm.  His case studies are well researched, and his management of the military aspects of offensive power projection supports his argument well.  While his predictive methodology poses problems, and his definition of survival is questionable, the book provides value by allowing readers the space to evaluate where Mearsheimer’s analysis does not hold up and discuss alternative approaches to understanding conflict risk and contemporary political economy.