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5 See, for example, Gilpin, Robert, US Power and the Multinational Corporation: The Political Economy of Foreign Direct Investment (New York: Basic Books, 1975)CrossRefGoogle Scholar ; Waltz, Kenneth N., Theory of International Politics (New York: Random House, 1979)Google Scholar , Waltz, Kenneth N., ‘Structural Realism after the Cold War’, International Security, 25:1 (2000), pp. 5–41CrossRefGoogle Scholar ; Wohlforth, William C., ‘The Stability of a Unipolar World’, International Security, 24:2 (1999), pp. 5–41CrossRefGoogle Scholar ; Mearsheimer, John, The Tragedy of Great Power Politics (New York: W. W. Norton, 2001)Google Scholar ; Layne, Christopher, ‘A New Grand Strategy’, The Atlantic Monthly, 289:1 (2002), pp. 36–42Google Scholar ; Layne, Christopher, ‘America's Middle East grand strategy after Iraq’. Review of International Studies, 35:1 (2009), pp. 5–25CrossRefGoogle Scholar ; Campbell, Craig, ‘American power preponderance and the nuclear revolution’, Review of International Studies, 35:1 (2009), pp. 27–44Google Scholar ; See also the 2009 special issue (no. 1) of World Politics in which nine authors explore the impact of the unipolar distribution of capabilities in the contemporary international system on the behaviour of the dominant state and on the reactions of other states.

6 See, for instance, the literature on the democratic peace theory including Maoz, Zeev and Russett, Bruce, ‘Normative and Structural Causes of the Democratic Peace’, American Political Science Review, 87:3 (1993), pp. 624–638CrossRefGoogle Scholar ; Russett, Bruce, Grasping the Democratic Peace: Principles for a Post-Cold War World (Princeton: Princeton University Press, 1993)Google Scholar . See also, for a useful critique of the democratic peace thesis, Barkawi, Tarak and Laffey, Mark (eds), Democracy, Liberalism, and War: Rethinking the Democratic Peace Debate (Boulder, CO: Lynne Rienner, 2001)Google Scholar .

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19 Tang, Shiping, ‘Taking Stock of Neoclassical Realism’, International Studies Review, 11:4 (2009), p. 802CrossRefGoogle Scholar . Much the same can be said about the works of a Realist-Liberal synthesis. See, for example, Papayoanou's 1996 articles on economic interdependence, domestic institutions, and the balance of power. Papayoanou, Paul A., ‘Interdependence, Institutions, and the Balance of Power: Britain, Germany, and World War I’, International Security, 20:2 (1996), pp. 42–76CrossRefGoogle Scholar .

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26 For more on this, see Jensen, Lloyd, Explaining Foreign Policy (NJ: Prentice-Hall, 1982), pp. 10–12Google Scholar ; Neack, Laura, The New Foreign Policy: US and Comparative Foreign Policy in the 21st Century (Rowman and Littlefield, 2003), pp. 8–15Google Scholar .

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29 They include cognitive consistency theory, schema theory and cognitive mapping. For a useful exploration of subtle differences among them, see Young, Michael D. and Schafer, Mark, ‘Is There Method in Our Madness? Ways of Assessing Cognition in International Relations’, Mershon International Studies Review, 42:1 (1998), pp. 63–96CrossRefGoogle Scholar .

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38 Here I draw upon the insights of the ‘critical realist philosophy’ of Roy Bhaskar (1978) and the ‘structuration theory’ of Anthony Giddens (1979). Although they draw different implications from the relationship between structure and agent, they share the common ontological core: structures and agents in the social world are internally related. See Giddens, , Central Problems in Social Theory: Action, Structure and Contradiction in Social Analysis (London: Macmillan, 1979)CrossRefGoogle Scholar ; Bhaskar, , A Realist Theory of Science (Hassocks: Harvester Press, 1978)Google Scholar .

39 In this vein, rather than deterministic forces, the concept of cause in IR needs to be understood as ‘influences’ which do not have deterministic connotations: it is quite common for us to talk about someone exerting their influence but to no avail, so the concept of ‘influence’ does have a non-mechanistic meaning.

40 In this regard, I am against the position put forward by Hollis, Martin and Smith, Steve in ‘Two Stories about Structure and Agency’, Review of International Studies, 20:3 (1994), pp. 241–251CrossRefGoogle Scholar . See also, Hollis, Martin and Smith, Steve, ‘Beware of Gurus: Structure and Action in International Relations’, Review of International Studies, 17:4 (1991), pp. 393–410CrossRefGoogle Scholar . Their proposition that ‘there are always two stories to tell about the agency-structure debate’ is an epistemological stance which is trapped into the positivists' narrow and mechanistic understanding of cause in which causes are treated as deterministic (‘pushing and pulling’) forces working only in a ‘when A, then B’ manner. This is problematic especially in the causal study of the state's behaviour in global politics given the fact that the state's foreign behaviour invariably derives from multiple sources operating in combination: recall the ontologically interrelated relationship between the agent and the structure. There are complexity and variety intrinsically involved in world political causality. For this reason, as already mentioned (see fn. 39), causes are understood here as ‘influences’ which do not have deterministic connotations. As regards how to conduct an empirical analysis with the non-mechanistic and broad conception of cause, I discuss in detail in the next section.

41 Certainly, there have been integrated studies on foreign policy and attempts to develop integrated theoretical frameworks. See, for example, Rosenau, James N., ‘Pre-theories and Theories of Foreign Policy’, in Farrell, Barry (ed.), Approaches in Comparative and International Politics (Evanston: Northwestern University Press, 1966)Google Scholar ; Brecher, Michael, The Foreign Policy System of Israel: Setting, Images, and Process (New Haven: Yale University Press, 1972)Google Scholar ; Mintz, Alex, ‘How Do Leaders Make Decisions?: A Poliheuristic Perspective’, The Journal of Conflict Resolution, 48:1 (2004), pp. 3–13CrossRefGoogle Scholar . Yet these studies are more in the nature of exceptional examples rather than representative cases in a generally accepted research method in the field of IR.

42 Hermann, Charles F., ‘Epilogue: Reflections on Foreign Policy Theory Building’, in Neack, Laura, Hey, Jeanne A.K., Haney, Patrick J. (eds), Foreign Policy Analysis: Continuity and Change in Its Second Generation (Englewood Cliffs, NJ: Prentice Hall, 1995), p. 247Google Scholar .

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47 See, for example, Kurki, Milja, Causation in International Relations (Cambridge: Cambridge University Press, 2008)CrossRefGoogle Scholar .

48 For a similar critique, see Hall, Ian, ‘What Causes What: The Ontologies of Critical Realism’, International Studies Review, 11:4 (2009), pp. 629–630CrossRefGoogle Scholar .

49 Rob Stones notes that those engaged in a strict and formal form of deductive logic, known as ‘deductive-nomological’ modelling tend to write in an all-knowing, somewhat ‘omnipotent’ manner about events, but this implied knowledge is not matched by the levels of such confidence. See Stones, , Sociological Reasoning (London: Palgrave Macmillan, 1996), p. 83CrossRefGoogle Scholar . Going a step further, Robert Jervis comments that even scholars who use large N clusters of data ‘often look at many cases to see if a proposed generalisation fits the data. [But] this is a form of confirmation, not the discovery of new facts’. See Jervis, ‘Pluralistic Rigor’, p. 146.

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52 Carlsnaes, Walter, ‘The Agency-Structure Problem in Foreign Policy Analysis’, International Studies Quarterly, 36:3 (1992), p. 256CrossRefGoogle Scholar .

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56 Here no attempt is made to provide a comprehensive list of all possible causal variables of states' external behaviour; many possible causal factors have already been described in previous works (see, for example, Rosenau, Pre-theories; Brecher, The Foreign Policy System of Israel). There is no need to recount them here. As noted, my intention in this article is to elaborate on how to utilise a multicausal approach and to make clear what ontological and epistemological assumptions and premises should be made before using it.

57 For classic illustrations of this method, see George, Alexander L., ‘The “Operational Code”: A Neglected Approach to the Study of Political Leaders and Decision-making’, International Studies Quarterly, 13:2 (1969), pp. 190–222CrossRefGoogle Scholar .

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65 Brecher, Michael, ‘International Studies in the Twentieth Century and Beyond: Flawed Dichotomies, Synthesis, Accumulation, ISA Presidential Address’, International Studies Quarterly, 43:2 (1999), pp. 213–215CrossRefGoogle Scholar , emphasis added.