This paper examines the evolution of international security theory from the Cold War to the globalized post-9/11 world. It analyzes three major theoretical frameworks — classical realism, neo-realism, and critical security theory — tracing their core assumptions about state behavior, power, anarchy, and cooperation. Drawing on the work of Morgenthau, Waltz, and critical theorists, the paper evaluates how each paradigm accounts for the changing nature of international relations, including the rise of non-state actors, economic interdependence, and humanitarian concerns. The paper concludes that no single theory fully explains contemporary international security, and that a balance approach drawing on critical security offers the most viable framework for the early twenty-first century.
With the end of the Cold War and the bipolar global order, an "international community" — as portrayed by increased transnational cooperation and globalization — has evolved. However, the integrity of this community depends on the actions of each individual member. Prior to 1989, the two great powers of the world, the United States and the Soviet Union, countered each other, creating a balance of power. This, in turn, polarized other states that fell under each respective power's umbrella of security and economic stability. After the collapse of the Soviet Union, however, the power of the United States led to hegemonic stability.
During the Cold War, the United States used "national security" as justification for its actions in the international arena. National security was used by internationalists to advocate increased American involvement in international affairs, yet it was also the reason isolationists promoted self-reliance and separation from global issues. If there are no restrictions on states' military capabilities, the state with military superiority will dominate all facets of global affairs — both political and economic. The economic stage is a zero-sum game, and without cooperative regulation the disadvantaged developing world would suffer at the hands of developed nations (Viotti and Kauppi 2006).
In the contemporary world, states' international agendas are no longer dominated by military security. Policies that are considered domestic now affect matters on a global basis. For example, despite U.S.-based multinational corporations' independence from American laws through international operations, any restrictions imposed upon them by the U.S. government could adversely affect that corporation's interests in another country. This may lead to economic suffering even though the policy is applied domestically within the United States. This change is germane when viewing the world through the theoretical lens of international relations, specifically through the paradigms of realism, neo-realism, and critical security (Nye 2006).
Since the end of World War II, realism has dominated the field of international relations. As a distinct school of thought, realism places its emphasis on the state as the primary actor in world politics. Realists generally hold a pessimistic view of human nature and a conviction that international relations are necessarily conflictual, with international conflicts ultimately resolved by war. Realists operate with the core assumption that world politics unfolds in a system of international anarchy — a system with no overriding authority and no world government. As a result, international relations can be defined as a struggle between power-maximizing states in an anarchical environment (Morgenthau 2005, pp. 2–8). For this reason, realism is sometimes referred to as the power politics school of thought.
The ideas of realism date as far back as Thucydides, whose History of the Peloponnesian War is recognized as the first attempt to explore conflict in terms of the dynamics of power politics. Within this structure, the prioritization of national interests over ideals or ethics seemed somewhat contradictory to the emerging Athenian philosophy (Rose 1998). However, "modern realism" is usually distinguished between the classical realism of E. H. Carr and Hans Morgenthau, and the neo-realism of Kenneth Waltz.
For the realist, based upon the views of Carr and Morgenthau, the following key assumptions are made:
The international system is anarchic. There is no authority above states that is capable of regulating or curbing their actions and interactions. States must relate to other states on their own, rather than having rules dictated to them by some higher entity.
Sovereign states are the main actors in the international system. Global institutions, non-governmental organizations, multinational corporations, individuals, and sub- and trans-state actors are independent and have little long-term effect on state-to-state relationships.
States naturally strive to amass needed resources in order to pursue national security. Each state has an overriding interest in its own national security — in effect, the interest in preserving itself. Levels of power, typically economic and military, characterize the bulk of relations between states.
No universal principles of statecraft exist that are viable and usable for all states. Geography, chronology, and numerous other factors influence statecraft independently of fixed maxims. If morality is introduced into statecraft, reckless commitments, diplomatic arrogance, and the potential for emotional escalation of conflict often result (Carr 2001; Morgenthau; Williams 2008).
This is a rather Hobbesian perspective — the strong-state theory — and focuses on the competitive nature of humanity. Unless conditions are ripe for cooperation, states, as well as individuals, have no real reason to cooperate. States, again like individuals, are inherently aggressive, territorial, and act upon their own motives for self-preservation and the perpetuation of the state itself. Security, then, is a zero-sum game in which only relative losses and gains can be made, and the rise and fall of the security dilemma between states is inevitable.
Since realism is so state-centric and individualistic, can ethics ever be a part of state relations? Ethics in international relations are very different from those in the public sphere. A political leader does not have the freedom to act as a private citizen might. This is because a political leader is responsible to the people of his or her country. To follow a prescribed set of personal ethics would therefore be irresponsible and would constitute a moral failure, because political leaders bear a very heavy responsibility for the security and welfare of their country and its people (Mearsheimer 2008). States should therefore not impose their ideals onto other states; that activity is dangerous and threatens the balance of power and security of both nations. It is this pessimistic understanding — that humans are not what we might want them to be, but as they always have been, with only technology and expression having evolved — that forms the heart of the realist approach to statecraft. Thus, statecraft is a sober and uninspiring activity that involves a profound awareness of human imperfection (Waltz 2008).
Neo-realism is led by Kenneth Waltz. His seminal work, Theory of International Politics (1979), is referred to as "the most far-reaching theoretical attempt so far to reestablish, albeit in more rigorous form, the central tenets of realism." The real significance of Waltz's theory, however, lies less in his initiation of a new theoretical line than in his translation of the methodology into a form that is more distinct and more useful than the overriding theory itself (Keohane 1986).
Waltz's neo-realism maintains many of the basic features of classical realism, such as power as a central concept and independent states existing and operating in a system of international anarchy. However, Waltz departs from that tradition by setting aside its normative concerns and by attempting to provide a scientific theory of international relations. There is no discussion of human nature in his framework; the focus is instead on the structure of the system rather than the human beings who create and operate it. According to Waltz, the realm of international politics never changes but has always been a realm of necessity and violence (Baldwin 1993, p. 15). To explain this continuity, Waltz directs his attention to the structural characteristics of an international system of states rather than to its component units. Waltz's concept of structure refers to the hierarchical ordering of a system (Waltz 1979).
Classical realism concentrates on the units and their functional attributes but is unable to account for changes in behavior or in the distribution of power that often occur independently of fluctuations within human beings themselves. Neo-realism, on the other hand, explains how structures affect behavior and outcomes regardless of the characteristics of power and status. States, then, should be treated as functionally similar units because their goals are similar, and the analysis becomes more concerned with the coordination — psychological, if you will — of the mechanisms of interaction (Jervis 2008).
"Post-Cold War challenge to state-centric security paradigms"
"Applying rival theories to post-9/11 international conflicts"
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Rose, G. 1998. "Neoclassical Realism and Theories of Foreign Policy." World Politics 51(1): 144–72.
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