What explains the dominance of realism in international political theory?

Realism is broadly accepted to be the dominant theory in international relations, since the inception of the subject as we currently understand it. Other theories have mainly developed as an evolution, or rejection, of realist principles; and some of the greatest political decisions of the 20th century were taken in accordance with realist thinking. But how can a single view have been so dominant, and remain so till the present? This essay will argue that the answer is multi-faceted, covering topics such as the evolution of the theory, its applications in political rhetoric, and how realism has been, more often than not, predictive of major international events. 

Before analysing realism’s dominant position, we must understand the true nature of the theory. It was a development of ideas common throughout history, such as the primacy of power and the competitiveness of groups to attain it. In particular, realism examines the world at the state level, describing them as the main, or only, units of importance on the world stage. While they may not have understood the ‘state’ in the same way, thinkers such as Thucydides and Machiavelli would have appreciated modern realism’s essential tenets. It can be thought of as a reaction to the idealism of the 'inter-war’ years (1919-1939), which stressed the basic good of human nature, and believed that a global peace was possible. With the outbreak of the Second World War, flying in the face of idealist predictions and efforts, a new theory was sought. This, which we call realism, was far more negative about man’s true nature. It points to a deep desire for power, and relegation of other goals until achieving it. Expanded to the international stage, this stresses the dominance of power as the guiding principle for states, and explains their competitiveness to attain it. 

In particular, essentially all strands of political realism retain the 3 essential ’S’s: “statism, survival and self-help”. Realism takes the nation-state to be the main, and sometimes the only, unit worth considering. Above the state, the world is anarchic; below, there are no groups with power to rival that of the state. Weber said that a state could only exist if it had the “monopoly of the legitimate use of force within a given territory”, which supports this view.(Weber, 1918) States seek to maximise their own power wherever possible in classical realism, and maximise security among states of different capabilities in structural realism. 

As Machiavelli (Il Principe, 1513) pointed out, the first priority of the state must be its own survival. This requires maximising power and security, and trumps all other goals. A new moral code is provided, based on the idea that there are no universal ethics. In terms of self-help, as the global situation is anarchic, each state must help itself. Treaties can be made, but must not be depended upon. In the end, the state must build up its own military and other forces, in preparation for attack. This, of course, can lead to the security dilemma. As one state builds up its arms, another fears attack and increases the power of its military, leading to an endless upward spiral of fear and military build-up. Realism therefore discourages countries from depending on other, non-national sources of security, such as NATO/the UN, or peace agreements. 

One of the main reasons why realism has been so dominant over time has been its ability to evolve and develop, in response to academic rigour and world events. Even within the “6 Principles of Political Realism”, outlined by Hans J. Morgenthau, one of realism’s founding thinkers, there is ample space for change.(Morgenthau, 1967, p.4-14) The third principle notes that the meanings of 'interest’ and 'power’ are not “fixed once and for all”. This allows the theory to reaffirm its core beliefs over time, while tweaking definitions to explain new political developments. For example, in history power has generally been used as a rather narrow idea, resting mainly on the size and capabilities of armed forces. Today, most will accept that power is a far more complex and fluid concept, which can be projected from any number of economic, military, social, cultural or other factors. With such a wide platform, it isn’t hard to see how realism can claim to be relevant to a huge swathe of international political activity. 

The power of evolution can also be seen in newer theories of realism, deviating from the classical original to fix perceived flaws or explain specific circumstances. For example, some have criticised realism for its focus on the state and the military, and for a lack of scientific rigour.  Neo-realism (or structural realism), such as espoused by K. Waltz, sought to meet some of these criticisms. It looks at the structure of international politics, involving a degree of co-operation as well as conflict. The key variable here is the distribution of capabilities across states. They are all functionally similar, with the same aims and priorities, merely differing by the ability to meet those aims. Capability refers to military, political and economic strengths. Waltz’s ideas have been called defensive realism, as they see states as security maximisers, even at the expense of some power. This contrasts with more recent offensive realism, believing that states want to maximise their power at all costs. There is no status quo level of power distribution, so the quest for more power is perpetual and only limited by the capabilities of states. Followers of Morgenthau, such as Schweller, have reacted to neo-realism with their own neo-classical realism. This argues that states differ in interests, and domestic policies matter, so states cannot be seen as functionally similar units. There are further models, such as rational choice realism, where states are utility maximisers, and co-operation is possible and useful. 

Clearly, over the last half-century realism has seen extensive updating and critical analysis, which serve to strengthen its core ideals. The fall of the USSR did provoke a flurry of critiques, as it seemed to fly in the face of realist theory. How could a powerful country, with a huge military and possibility for further expansion, simply implode and retreat? However, rather than destroy realism, the criticisms mainly served to refine the theory, with the last decade being a particularly productive time for the development of new realist thinking. 

Realism theory sees armed conflict between states as the inevitable consequence of their hunger for power and territory. Other theories, with more co-operative or pacifist outlooks, find it harder to explain why the world expends so much of its resources on warfare. This can be seen as an advantage of realism, in describing how the world really is rather than how it “should” be. Practicality is important for a theory which seeks to predict future events and therefore help devise strategies. Furthermore, the theory provides contains certain favourable qualities for political leaders, which have ensured its importance outside of academic circles. Realism’s main tenets can be easily understood, and applied to real-world events. The tactics it promotes, such as favouring the 'national interest’ above all, are both politically palatable and useful sound-bites. Promoting the ends decreed by other theories, such as unilateral disarmament or favouring regional over national benefits, can be far harder for a politician to contemplate. 

Realism emerged soon after the Second World War, and has remained dominant to this day. Such a testament could also be applied to the United States of America, which has enjoyed a similarly powerful position over the last 60 years. Many proponents of realism have been American, including persons within the American government (for example, Henry Kissinger). It could be argued that a symbiotic relationship has existed, with America following realist ideals, in exchange for its success validating realist theories. With the fall of the USSR, the US is the world’s sole true superpower, and this encourages the use of realism in other states looking to emulate its success. In a broader sense, the theory favours powerful nations, which also happen to contain most of the academic world. When evaluating the dominance of a theory, such geographical issues cannot be overlooked. Whether for intentional or sub-conscious reasons, the favoured theories of major Western powers do tend to favour the current power balance.

In conclusion, realism has remained the main theory of international relations through its evolution; applications in 'realpolitik’ and justifications for warfare; and particular state relationships. Its dominance may well be challenged in the future, through significant non-state actors on both the supra- and sub-national levels; but for the moment it appears to be in rude health.