An Unwritten Future: Realism and Uncertainty in World Politics, Princeton University Press, 336pp, £35

I will say some bluntly critical things. But before that, this is an important book. Kirshner throws down a gauntlet, with urgency and clarity, at a time when Vladimir Putin’s violence puts power politics back under public discussion. It is a rich and erudite work, moving dextrously from history to economics to literature in ways that few scholars could match. His chapter on what a realist political economy would look like is fascinating and original. Everyone should get the book on their reading list. Ultimately, though, as a broadside against realism that sailed out of more recent shipyards, it misfires.

Realism sees the shadow of war as the world’s defining, inexorable feature. As there is no higher authority committed to protecting us, ours is a harsh world in which war and predation is possible, where others’ intentions are uncertain, and where humans are capable of barbarism without limit. We, as organised polities, are therefore precariously on our own. This ultimate solitude puts a premium on power, primarily military and coercive power. Cooperation is possible, but fragile and impermanent. The most important currency, and differentiating variable, between states is the distribution of capabilities. The imperatives of anarchy strongly incentivise most states towards similar behaviour, namely mutual balancing and sameness. We cannot replace this state of anarchy with benign hierarchy, world government, or democratic peace. It’s not a nice theory. But it’s not a nice world.

For Kirshner, realists increasingly fell prey to a disastrous intellectual reductionism. There was once a vital tradition, ‘classical realism’. Classical realists, from Thucydides to modern political thinkers such as Raymond Aron and Hans Morgenthau, tempered their sense of the fundamentals with awareness of the forces that make the world a hard place to navigate: historical legacies, uncertainty, contingency, and exogenous shocks. Things went south when more recent ‘neo’ or ‘structural’ realists abandoned their classical inheritance, beguiled by ahistorical, hyper-rational models of behaviour. Approaching international politics as a systematic science, gripped by physics (or economics) envy, they coveted analytical austerity at the price of complexity, and perverted the tradition. The offending realists are hardly aware of states’ capacity for irrational behaviour, for great power hubris, or their variety of purposes, such as the craving for honour.

A few objections are due. Who precisely are we talking about? Beyond Kenneth Waltz, John Mearsheimer and Stephen Walt (the latter is a harder case, as his work incorporates variables below the distribution of power), other accused realists are rarely named. Largely missing from the index, and the action, are scholars whose work is partly or wholly inspired by the attempt to put realism on a social-scientific footing: Shiping Tang, Barry Posen, Randall Schweller, Susan Martin, Colin Dueck, Christopher Layne, Steve Lobell, Joseph Parent, William Wohlforth, Dale Copeland, Joshua Shifrinson, Sebastian Rosato, Jonathan Monten and beyond. Each is mindful that states at times do not behave as they ‘should’ as realists under anarchy, and the penalties that follow. Put simply, to claim that the problem of ‘great power hubris’ is ‘invisible’ to them is a silly overstatement.

Secondly, smarter versions of structural realism do not simply say all states are always ‘identical’. They suggest, rather, that anarchy incentivises them towards a general convergence and similarity, but leaves it open for them to do ‘damn fool’ things. Realists expect reckless behaviour, such as under-balancing or ambitious peripheral wars, to attract punishment. To show that Thucydides allows for multiple influences on Athenian behaviour is not the ‘slam dunk’ the author thinks. And after all, Waltz and Mearsheimer opposed America’s consequential military adventures, in Vietnam and Iraq respectively, arguing such ill-conceived expeditions would harm the national interest. Realists have more work to do, to explain why the leading states that rose to pre-eminence can then lose their heads. But the literature Kirshner lampoons is not primitive ‘billiard ball’ stuff. The stronger critique of the Waltzian tradition is not that it is deterministic in its causal claims, but consistent with a range of outcomes and under-determined.

Focussing his fire on a few familiar targets, Kirshner overlooks realist literature where authors demonstrate the workings of international power structures on diverse cultures, from Arthur Eckstein’s study of ancient Roman imperialism, Yuan-Kang Wang’s study of Ming China’s use of force, or Errol Henderson’s study of realism in post-colonial Africa. These scholars argued through a close reading of historical primary sources that anarchy did indeed exert shaping and shoving pressures on the state. To be a structural realist and a historian is not antithetical.

Kirshner uses the phrase ‘analytical modesty’ seven times. Intellectual humility he regards as a facet of the classical tradition. It’s a reasonable stance to take, but taking it sets a standard by which an author will be judged. Kirshner embraces the virtue of modesty up to the point where he has opinions. At that point, his pen sharpens. We hear ‘neo’ realism is ‘failed’, part of a ‘ruinously unproductive’ turn in the social sciences, that ‘paradigm wars are largely vacuous’, that looking at states as actors distinguished ‘only by their relative capabilities’ is ‘utterly and irretrievably incapable, on its own, of explaining behaviour in world politics.’

There is not even a gesture, here, to humility, or to the possibility of any ‘first cut’ value in a structural account of world politics. In challenging the unrewarding oversimplifications of realism, Kirshner commits the opposite error. He admires complexity. Structural realism overlooks some nuance. But a fixation with nuance can also distort judgement, replacing a crude map with such layered detail that the map is almost ‘to scale’, making it no map at all. Kirshner argues for incorporating domestic, ideational and ‘historical chaos’ variables into the picture, heavily weighting agency and historical peculiarity. But the net result is to dilute realism of its main analytical priority so much that it turns it into a sort of liberal internationalism with an eye to the importance of power.

This approach fails the China test. A structural account of world politics would begin with China’s sheer relative size, its precipitous economic growth, and its accelerating acquisition of military capabilities. It would predict that this major power shift would increase China’s appetite for security, leading to ever more aggressive territorial claims, its demands for deference, its bullying of neighbours and its sabre rattling. It now does these things.

Indeed, realists who put most weight on the distribution of power foresaw this more clearly than the nuance brigades who find paradigm wars beneath them. Those brigades assured us, decades ago, that China’s trajectory was more complicated, that globalisation or norms or international institutions or the soft attractions of western culture or East Asian strategic heritages would prevent the return of hard-edged geopolitics, that Beijing would be content to get rich without trying to overturn American-led security order. The realists Kirshner writes off as analytically negligent called the most consequential change in world politics right.

Despite his pleas for sensitivity towards history’s predicaments, Kirshner pours contemptuous, hyperbolic language on Prime Minister Neville Chamberlain and interwar Britain. There is this passage: ‘most of the elites directing British foreign policy in the 1930’s were comfortable with the notion of a fascist Germany dominating the continent.’ Hold it right there. A minority of elites did, but the elites directing foreign policy, like Chamberlain, began rearmament against such dangers and were vilified for doing so. They prioritised air power, and its projection in particular over British and European skies, to guard against the threat they explicitly designated as the most grave, the Third Reich, and at the expense of protecting their empire beyond Europe. Had they been ‘comfortable’ with a Hitler-dominated Europe and the overturning of the balance of power, they hardly would have declared war after the invasion of Poland. Recall too that this was an hour when the Soviet Union was in a de facto alliance with Nazi Germany, and America stood aloof. Yet Kirshner treats Britain, the empire that held the ring between the fall of France and the invasion of the Soviet Union, as the main problem.

We hear that Britain ‘placed itself within a hair’s breadth of brutal subjugation’ by Germany. This is excessive, given Britain’s naval strength in home waters; the impossibility of Hitler’s Operation Sea Lion; the fact that it was blockading Germany in 1940, not vice versa; and its industrial advantages, still outproducing Germany in aircraft. Washington eventually threw its weight behind Britain precisely on the basis that it was a strong enough horse, worth backing. Material capabilities and military balances don’t tell us everything, but are a good start.

Kirshner scorns deterministic theories that seek straight analogies about war-prone power shifts from Sparta-Athens to China-America. Yet when it suits him, Kirshner is happy to borrow from Thucydides, in passing: ‘On the ‘debate’ over Iraq, one can hear the clear echoes of Sicily.’ If an ancient debate about invading Sicily leaves echoes about invading modern Iraq, why can’t we draw from Thucydides’ theme of power shifts an echo for the looming collision in Asia? Prudential realism, Kirshner claims, warns against hasty retrenchments leading to dangerous power vacuums in Europe and Asia. Yet Kirshner advocates a drawdown from the Middle East, ignoring his own counsel.

Despite emphasising change in international relations, Kirshner urges a status quo conservatism about US commitments in Europe and Asia, warning against a destabilising change but saying little about how Washington should adapt. This is a policy agenda based on the stable unipolar hierarchy of 1991-2008, rather than the disequilibrium and multi-level crisis that is now underway. He criticises realists for not giving positive advice, but his advice amounts to ‘it’s complicated, so be careful.’ That’s a low return on a large intellectual investment.

What are we to conclude? Not that structural realism out-performs classical realism, or with calls for this or that variant of realism to predominate. Rather, it is surely time to abandon the overblown distinction that both Kirshner and his targets assume, the alleged sharp divide between classical and structural realism. The primacy of structure and security-seeking, and the tendency of rivals to imitate one another, are not modern but ancient themes, articulated in different vocabularies. They were common to the causal hierarchies identified by Morgenthau, Herz and Niebuhr, the very realists who inspire Kirshner. Historical actors had multiple motives, but structure bore down upon them. If the world needs anything from realists now, it is not an intramural brawl setting Morgenthau against Mearsheimer, but a reaffirmation of realism’s essential unity. If our world is an inherently constrained world, that makes it imperative to cultivate and apply power within those constraints. The future may be unwritten, but it is not unbound.