What is the problem with aggressive realism in international relations?

 

Before I outline John Mearsheimer’s theory of aggressive realism, I will present my version of the classical liberal view of international relations.

A classical liberal view

As the epigraph might suggest, I subscribe to a view of international relations that has been around, in one form or another, at least since the time of the Ancient Greeks. The poet Hesiod, one of the founders of Greek epic poetry, advised his brother, Perses, to avoid thinking of obtaining wealth by engaging in predatory violence, including war. He urged Perses to respect the rights of other people, and to seek prosperity by working and engaging in peaceful competition with economic rivals.

As I see it, it is natural for individuals to seek to flourish by engaging in peaceful pursuits in mutually beneficial collaboration with others. However, it is an unfortunate fact of life that some people - individuals, groups, and nations - seek to obtain wealth by predation. People can flourish by engaging in peaceful pursuits only if they are able to protect themselves from predation.

It is not difficult to identify predatory nations which have a recent track record of seeking to invade the territory of other jurisdictions or threatening acts of violence against them. 

People in neighboring jurisdictions have an obvious incentive to protect themselves, and each other, from such predatory behavior. Nations that do not have predatory intent toward other jurisdictions have an incentive to band together to form communities of peaceful nations. The purpose of these multinational communities is to establish and enforce international rules that outlaw invasion and other violent activities that predatory nations undertake.

The multilateral communities of peaceful nations (MCPN) that I have in mind would have more in common with some existing security treaties than with the United Nations. I envisage that the MCPN would exist solely for mutual protection and would avoid attempting to pursue other objectives such as protecting individual rights, promoting economic development, or pursuing environmental objectives.  Multilateral cooperation might be desirable to pursue some of those other objectives, but the MCPN are more likely to be effective in pursuing the objective of discouraging predation if they focus specifically on that objective.

The approach proposed above should enable liberal democracies to avoid becoming involved in pathetic attempts to impose the institutions of liberal democracy on people with different belief systems, values, and ideals. However, it would support provision of military aid to Ukraine - to support its defense against Russian aggression, to Israel - to support its defense against terrorism sponsored by Iran, and to Taiwan - to counter Chinese threats of invasion.

I have previously outlined some similar ideas in myreview of Christopher Coyne’s book, In Search of Monsters to Destroy.

The approach proposed here has much in common with the classical liberal approach to international relations theory described by Edwin van de Haar in a monograph entitled, Human Nature and World Affairs, published by the London-based Institute of Economic Affairs in 2023.

The theory of aggressive realism

When a friend suggested a few weeks ago that I should watch Lex Fridman’s interview of John Mearsheimer, my initial reaction was that I had already knew enough about Mearsheimer’s views because someone had referred them to me in 2022, soon after Russia’s invasion of Ukraine. I suggested that my friend should take a look at Niall Ferguson’s refutation of Mearsheimer. Surprisingly, he took up my suggestion, so I felt obliged to watch the Mearsheimer interview.

After watching the interview, my initial reaction was that I had heard enough from John Mearsheimer to last me for at least the rest of 2025. However, I had to acknowledge (to myself) that Mearsheimer’s approach to the issues was scholarly, So I decided that it might be worth trying to find out more about the basis for his views. That is how I came to read, The Tragedy of Great Power Politics (2014 edition).

Mearsheimer argues that the overriding goal of each state is to maximize its share of world power. Since no state is likely to achieve global hegemony, the world is condemned to “perpetual great power competition”.

His theory of aggressive realism is based on 5 bedrock assumptions:

1. The international system is anarchic, in the sense that the system comprises independent states that have no central authority above them. 
2. Great powers inherently possess some offensive military capability. 
3. No state can ever be certain about another state’s intentions, regarding the use of offensive military capability.
4. Survival is the primary goal of great powers – they are unlikely to be able to pursue other goals if they are conquered.
5. Great powers are rational actors – they think strategically about how to survive in their external environment.

Mearsheimer argues that these assumptions are realistic and that, together, they “create powerful incentives for great powers to think and act offensively with regard to each other”.  He suggests that hegemony is the best way for any state to guarantee its own survival.

The author views aggressive realism as a prescriptive theory as well as a descriptive theory. If great powers want to survive, they should behave like aggressive realists.

The extent to which states fear each other determines the severity of their security competition as well as the probability that they will fight a war. An “unbalanced multipolarity” is the power configuration that generates the most fear because it contains a potential hegemon which stands a good chance of dominating the other great powers in its region and the world.

Much of Mearsheimer’s book is devoted to marshalling historical evidence in support of his theory, but the final chapter focuses on a specific application of his theory. In that chapter, he seeks to answer the question: Can China rise peacefully?

Mearsheimer does not believe China can rise peacefully. He argues that if China maintains rapid economic growth over the next few decades, it is likely to end up in an intense security competition with the United States and its neighbors. He views China as a potential hegemon and the current international power configuration as an unbalanced multipolarity.

According to Mearsheimer, the optimal policy for the United States to adopt toward China is “containment”, rather than other alternatives including preventive war, pursuing policies aimed at slowing China’s economic growth, or seeking to weaken China by fomenting trouble within its borders. Containment means “keeping Beijing from using its military forces to conquer territory and more generally expand its influence in Asia”. Mearsheimer suggests that the U.S. should form a balancing coalition with as many of China’s neighbors as possible.

Where is the problem?

As I see it, there are two main weaknesses in Mearsheimer’s analysis. The most fundamental problem stems from assumption 3. In order to argue that aggressive realism is the optimal strategy for a state to adopt, I think it would be necessary to argue that there is always a great deal of uncertainty about the intentions of neighboring states, rather than just lack of certainty. Perhaps it is true that no state can ever be certain about another state’s intentions, but I think states can usually make well-informed judgements about the intentions of their neighbors. Australia and New Zealand, for example, can be sufficiently certain about their intentions toward each other, to refrain from adopting offensive postures in that relationship. I think the same has generally been true of relations between Canada and the United States over the last century, but the recent rhetoric of the U.S. president might suggest that Canada would be wise to begin to re-assess the probability that the U.S. will continue to respect its territorial integrity.

Those examples illustrate the point I want to make. It is possible to make probabilistic assessments about the intentions of other states from past behavior and the rhetoric of their leaders. Some states obviously have peaceful intentions towards their neighbors whereas other states are currently engaged in predatory activities. In other instances, the probability of predatory behavior over the next decade might lie in the range from 0.1% to 1%; or from 90% to 100%; or in some other range.

The other weakness in Mearsheimer’s analysis seems to me to be an excessive focus on China as the potential hegemon. I agree with his analysis and policy prescription relating to China - as long as “containment” is pursued in a manner that can be presented to the Chinese government as a response to its aggressive policies toward its neighbors, rather than as an attempt to impede China's peaceful interactions with its neighbors.

 It seems to me, however, that communities of peaceful nations should be concerned to discourage all states from predation on their neighbors.  States that profit from predation have no incentive to stop until they assess that the costs of further predation are outweighed by the benefits. States in the neighborhood of Russia, Iran, and North Korea have good reasons to seek to contain the aggressive tendencies of those countries. Given that China, Russia, Iran and North Korea engage in military cooperation with each other, it would be particularly unwise for the U.S. and its allies to be unduly pre-occupied with responding to the rise of China.

Conclusions

John Mearsheimer’s theory of aggressive realism suggests that the over-riding goal of each state is to maximize its share of world power. He argues that there are powerful incentives for all great powers to act offensively with regard to each other.

The crucial assumption that Mearsheimer makes is that no state can ever be certain about another state’s intentions, regarding use of offensive military capability. I argue that it is possible for states to make probabilistic assessments about the intentions of other states based on past behavior and the rhetoric of their leaders.

It is not difficult to identify nations that have a recent track record of predatory behavior. Peaceful nations have an obvious incentive to band together to enforce international rules that outlaw invasion and other violent predatory activity.

Mearsheimer’s concerns about challenges that could arise from emergence of a new hegemon have led him to focus on the risks posed by the rise of China. While I agree with much of his analysis regarding the threat posed by China in the years ahead, it would be unwise for peaceful nations to overlook the threats currently posed by others (including Russia, Iran and North Korea) who clearly have predatory intentions toward other jurisdictions in their neighborhoods and are currently engaging in military cooperation in pursuit of their several objectives.