4. Of Billiard Balls and International Relations

Mearsheimer's quasi-Newtonian theory of state interaction

Mearsheimer calls his theory “offensive realism”, which is apt enough given its explicit legitimation of military aggression, if carried out to improve a state’s relative power position. It could equally aptly be called the “billiard ball theory” of international relations, reflecting its strangely mechanistic characterization of how states interact.

In The Tragedy of Great Power Politics, Mearsheimer argues that irrespective of how they rationalize their behaviour, major states follow the imperatives of offensive realism, though with some rare and unfortunate exceptions:

Realists tend not to draw sharp distinctions between “good” and “bad” states, because all great powers act according to the same logic regardless of their culture, political system, or who runs the government. It is therefore difficult to discriminate among states, save for differences in relative power. In essence, great powers are like billiard balls that vary only in size.

So, to understand state interactions in the international system, just imagine billiard balls of different sizes with the names of countries on them, big ones for the US and China, smaller ones for Russia, then Germany, Britain, and so one, down to tiny ones with Lithuania, Estonia, and so on.

Kind of like Newtonian mechanics. Colliding balls, responding deterministically, though with occasional departures from the laws of offensive realism, just as Newtonian physics has to be qualified by confounding factors like friction and air resistance.

Do you find that remotely plausible? Mearsheimer is obviously quite attached to the billiard ball metaphor and uses it repeatedly. If he hadn’t spelt it out explicitly in his main work espousing the offensive realism theory, you might have thought it was a caricature cooked up by critics of his theory. But there it is, in black and white.

It is not even remotely plausible. You can play with metaphors all you like. He opts for balls made of the same stuff, differing only in size. How about we allow some variability in ball composition? You could have some balls made of phenolic resin, like the real ones, or of rubber, or steel, or plasticene, or cement, each with different properties. So, why this particular choice of metaphor?

The underlying point he is trying to make is that state behaviour is determined by the structural features of the international system, having little or nothing to do with the internal features of each of the states, their different cultures, systems of governance, the personalities of their rulers.

The problem with this is that states, as such, don’t decide anything. “Russia” didn’t decide to invade Ukraine—Putin did. In each state, the locus of decision-making lies with the individuals, or groups of individuals, with the relevant powers. To suggest that their aspirations, fears, neuroses, ideological attachments, theories of how the world works, values, have no bearing on how they act is just absurd.

Putin could have responded to the putative threat of NATO in ways other than by invading Ukraine, but he chose not to. For him to have seen the matter as existential for Russia is ridiculous, and reflective of something about his mindset rather than the real world. Mearsheimer’s claim that he and other world leaders were trapped in an “iron cage”, effectively denied any agency, is also absurd.

Putin is at the top of the Russian power vertical, ruling a state which is accurately described as a “personalist” autocracy, a type of rule that has taken on much greater salience with the rise of Putin, Xi Jinping, Kim Jong-un, and Ayatollah Khamenei in Iran, the leaders of the coalition of autocratic states that now pose the most serious challenge to the democratic world since World War II.

Personalist autocracies display some distinctive behavioural features that distinguish them from collective forms of autocratic or totalitarian rule. A Brookings paper summed it up thus:

Among single-party dominated and military-led regimes, research shows that personalist authoritarians are the most likely to initiate conflicts abroad and pursue risky foreign policies. Not only are personalist authoritarians more aggressive abroad, they are also often unpredictable actors. With limited constraints on their power, personalist leaders are capable of carrying out volatile policies with little notice.

Does that seem familiar? No wonder the former president of Finland Sauli Niinistö recently lamented that he never thought he would pine for the old Soviet politburo. Niinistö’s point was that, for all its flaws, the politburo was a form of collective leadership that could restrain the actions of a leader who might wish to mark his place in history by taking dangerous initiatives with uncertain outcomes—like launching a war of territorial conquest against a neighbouring country.

Mearsheimer will have none of this. For him, it makes no difference to a state’s behaviour whether it is a liberal democracy, a one-party dictatorship, a personalist dictatorship dominated by a single individual, a military junta, a theocracy, or whatever. Nor, whether it is controlled by an amoral sociopath, or someone for whom departing from norms of decent behaviour is anathema.

Is that what he is really saying? Yes—he really says that. From the Tragedy of Great Power Politics:

The theory pays little attention to individuals or domestic political considerations such as ideology. It tends to treat states like black boxes or billiard balls. For example, it does not matter for the theory whether Germany in 1905 was led by Bismarck, Kaiser Wilhelm, or Adolf Hitler, or whether Germany was democratic or autocratic. What matters for the theory is how much relative power Germany possessed at the time.

Bismarck, Kaiser Bill, Hitler, no difference. To which presumably we could add Angela Merkel and Olaf Scholz, given whether Germany is democratic or not makes no difference. Would they have all invaded Poland in 1939? That seems to be the implication.

Mearsheimer does not hesitate to carry his theorizing up to, and beyond, the point of reductio ad absurdum, sticking with it even when it leads him to make some truly strange predictions. After all, a good theory ought to have some worthwhile predictive power. Quantum theory is very strange and implausible to many, and utterly incomprehensible to most, but it leads to extraordinarily accurate physical predictions.

Nonetheless, most international relations theorists baulk at getting too far into the prediction business, given all manner of uncertainties and the danger of ending up with eggs splattered on their faces. But not Mearsheimer. In 1990 he wrote a long essay for The Atlantic magazine titled Why We Will Soon Miss the Cold War.

In part, it was intended as a counterweight to the excessive optimism that followed the collapse of the Soviet bloc, exemplified by Francis Fukuyama’s claim that we had arrived at the “end of history”, by which he meant that the broad processes of humanity’s social and political evolution had reached a terminus, with liberal democracy and market economics the only viable options left standing. Fair enough—Fukuyama’s assessment certainly has not aged well.

However, Mearsheimer takes the argument much further, claiming that the democracies of Western Europe, the nations that for decades have been the core of the European Union and NATO, including Germany, Britain, France, Italy, would, after the ending of the bipolar division of the Cold War era, revert to type.

For centuries, these countries had been at each other’s throats, with a succession of major wars over territorial claims and other matters, and with the end of the Cold War, Mearsheimer predicted they would be likely to go at it again because: “the new Europe will involve a return to the multipolar distribution of power that characterized the European state system from its founding , with the Peace of Westphalia in 1648 until 1945”. Consequently:

The next forty-five years in Europe are not likely to be so violent as the forty-five years before the Cold War, but they are likely to be substantially more violent than the past forty-five years, the era that we may someday look back upon not as the Cold War but as the Long Peace.

Surely not? After all, these were all now stable liberal democracies, joined by a host of new democracies in central and eastern Europe. Unlike autocracies, especially personalist autocracies, they are subject to constraints on their power, and in the case of the older democracies have decades-long records of peaceful cooperation. A renewal of armed conflict between France, Britain and Germany, and other advanced European states seemed, and still seems, inconceivable.

This is illusory, argued Mearsheimer in his 1990 Atlantic piece. Once the binding glue of the threat posed by a common enemy, the Soviet Union and the Warsaw Pact, was gone, things would change dramatically. The term for this delusion, or what he thinks is a delusion, is the “democratic peace argument”, the idea that democracies are unlikely to go to war with one another. The democratic peace theory is an important  variant of the liberal internationalist framework to which realism in its various forms is counterpoised.

What is Mearsheimer’s evidence against the democratic peace theory? In his latest book, How States Think (2023) he cites a study by Zeev Maoz and Bruce Russett, who note that “If states come to believe that their application of . . . democratic norms would endanger their survival, they will act in accordance with the [violent] norms established by their rival.”

Actually, this paper strongly supports the democratic peace theory. From the abstract:

Using different data sets of international conflict and a multiplicity of indicators, we find that democracy, in and of itself, has a consistent and robust negative effect on the likelihood of conflict or escalation in a dyad.

The quote Mearsheimer uses makes the obvious point that in a situation where state survival is on the line, such as Britain in 1939, certain norms are likely to go by the board even in democracies, as with the unjust mass internment of ethnic Japanese in the US and the imprisonment of British fascists, temporary wartime measures. However, this is perfectly consistent with the generalization that democracies rarely initiate wars with each other.

Here was Mearsheimer’s take on the likely effect of the ending of the Cold War on the prospects for peace between the nations of Europe, from his 1990 Atlantic article:

If you believe (as the realist school of international-relations theory, to which I belong, believes) that the prospects for international peace are not markedly influenced by the domestic political character of states—that it is the character of the state system, not the character of the individual units composing it, that drives states toward war—then it is difficult to share in the widespread elation of the moment about the future of Europe.

He surmised that all sorts of bad stuff would start to bubble to the surface, especially from a reunified Germany:

Is it not possible, for example, that German thinking about the benefits of controlling Eastern Europe will change markedly once American forces are withdrawn from Central Europe and the Germans are left to provide for their own security? Is it not possible that they would countenance a conventional war against a substantially weaker Eastern European state to enhance their position vis-a-vis the Soviet Union?

So, yes, freed from the constraints imposed by the Cold War, modern Germany might well decide to invade Poland. And, judged by the criteria of Mearsheimer’s offensive realism theory, they would be right to do so!

Worse, he forecast that a nuclear arms race would break out in Europe, effectively killing the global non-proliferation regime. Except he thinks this might actually be a good thing:

The most probable scenario in the wake of the Cold War is further nuclear proliferation in Europe. This outcome is laden with dangers, but it also might just provide the best hope for maintaining stability on the Continent. 

If the most likely scenario of nuclear proliferation in Europe were to break out, he suggests, maybe the best thing would be to try and limit it to Germany, but failing this, let it run its course in Eastern Europe:

Proliferation should ideally stop with Germany. It has a large economic base, and so could afford to sustain a secure nuclear force. Moreover, Germany would no doubt feel insecure without nuclear weapons, and if it felt insecure its impressive conventional strength would give it a significant capacity to disturb the tranquillity of Europe.

But if the broader spread of nuclear weapons proves impossible to prevent without taking extreme steps, the current nuclear powers should let proliferation occur in Eastern Europe while doing all they can to channel it in safe directions.

So, nuclear proliferation in Europe would be not so bad provided, Mearsheimer says, it is well managed. What about what this would do for the broader non-proliferation regime in the rest of the world, not least in volatile regions like the Middle East? In any case, though, he is pessimistic that it can be well managed.

What to do then, in Mearsheimer’s characteristically pessimistic scenario? The answer is stunningly obvious—preserve bipolarity by keeping the Cold War going, somehow, but try to keep a lid on it so states don’t start nuking each other:

The implications of my analysis are straightforward, if paradoxical. Developments that threaten to end the Cold War are dangerous. The West has an interest in maintaining peace in Europe. It therefore has an interest in maintaining the Cold War order, and hence has an interest in continuing the Cold War confrontation. The Cold War antagonism could be continued at lower levels of East-West tension than have prevailed in the past, but a complete end to the Cold War would create more problems than it would solve.

Luckily for all of us, Europe especially, Mearsheimer’s prognostications have turned out to be almost comically inaccurate—Germany has not even considered invading Poland or any other nation—but is indicative of how in his mind his offensive realism theory had already congealed into an inflexible dogma.

The post-1945 history of Europe provides a powerful refutation of Mearsheimer’s insistence that the internal structure of states, their system of governance and the personalities of their rulers has no bearing on how they behave towards other states in the international system.

Pessimism, provided it is grounded in realistic assessments, may be appropriate, as is scepticism of utopian notions such as the idea we have reached “the end of history”. Mearsheimer however habitually takes pessimism to the point of morbidity, as with his prediction that war between China and the US is inevitable, a view that is grounded in his deterministic theory that states are doomed to behave like billiard balls, bound by his quasi-physical laws to act in certain ways.

Offensive realism is an all-round crock of a theory, a point that will be further underscored in the chapters that follow. It fails in terms of the realism of its premises, with its absurd simplification that the internal dynamics of states and his contention that the priorities and personalities of rulers and decision makers have little bearing on their decisions.

It fails as a predictive tool that provides useful guidance for decision makers, especially when it hardens into a dogma, as it has with Mearsheimer. And as a prescriptive tool it would be disastrous. If followed by all the major powers, it would be a prescription for endless wars.