International Relations. A self-Study Guide to Theory

Self-study (1) 
Now take some time and read chapters 2 and 4 of Waltz 1979: Theory of 
International Politics carefully. Why do reductionist theories fail as theo-
ries of international politics?
Reflect on the neorealist view that only a system’s level theory is a “real” 
theory of international politics. 
3.2. The neorealist concept of structure 
The alternative to reductionist theories conceptualized by Waltz is a specific 
type of system theory. It cannot be understood without discussing the concept 
of structure at the heart of this theory first. To think of any political system – 
national or international – in terms of its structure is the starting point of the 
neorealist theoretical program. This is why neorealist theory as formulated by 
Waltz is called “structural realism”. Please note that “structural” is different 
from “structuralism” (holism). “Structural” relates to the re-formulation of 
classical realism by introducing the concept of “structure” as part of the neo-
realist explanation; it is a structural realist explanation and will be discussed 
in detail below. In contrast, “structuralism” (holism, as introduced in Unit 2) 
relates to an ontological and methodological philosophy of science position. 

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For Waltz, structure is the system-wide component that makes it possible 
to think of a political system as a whole. His aim is to independently define 
the “elements” of a political system (national or international), to define 
structure on one hand and units and processes on the other. For him, this is 
necessary to “disentangle” causes of different sorts (that is, not to “mix” lev-
els of analysis) and to make possible a clear specification of structural causes 
and effects (Waltz 1979: 78). Defining structure independently of the “units” 
is necessary to explain the constraints that confine all states. The concept of 
structure serves the purpose of explaining why a certain similarity of behav-
ior is expected under systemic constraints. 
Following the definitional approach, structures have to be defined free of 
the attributes and the interactions of their units. The characteristics of the 
units (the type of political system, the types of political leaders, the social and 
economic institutions, the ideological commitments of states), their behavior 
and their interactions (the cultural, economic and military interactions of 
states) are not included in the definition of structure. They belong to the unit 
(state) level. This is an omission made in order to distinguish between varia-
bles at the unit level and variables at the system level (Waltz 1979: 80). The 
question of how to define a structure thus is simply a question of how units 
are “arranged” or positioned within the system (Waltz 1979: 80). For Waltz, 
the way the units/states are arranged or positioned is not a property of the 
units themselves but a property of the system. Waltz calls it a “positional pic-
ture” (Waltz 1979: 80).
In short, the structure of a system is defined by the arrangement of its