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Trust Building, Trust Breaking: The Dilemma of NATO Enlargement

  • Andrew Kydd

Barbara Koremenos, Charles Lipson, and Duncan Snidal conjecture that the conditions of membership in international institutions will grow more restrictive as a response to uncertainty about state preferences. Membership criteria will act as a signaling device—states more committed to cooperation will be willing to meet the criteria, whereas those less committed to cooperation will not. The recent enlargement of NATO to include the former Warsaw Pact members Poland, Hungary, and the Czech Republic illustrates this logic. The potential candidates for admission had to meet standards with respect to democratization, civilian control over the military, and the resolution of border and ethnic disputes with neighbors. These criteria served to identify the more cooperative potential members and to encourage cooperative behavior among those who aspired to membership. However, NATO enlargement came at a price. Although trust was built and cooperation fostered between the East European states that gained membership, trust was broken and cooperation harmed between NATO and Russia. This unfortunate outcome represents a dilemma that arises in the expansion of a security community: While expanding the security community enlarges the zone of peace and mutual trust, it may generate fear among those still on the outside, who view it as a potentially hostile alliance. I present a game-theoretic analysis of this dilemma and analyze the conditions under which it arises.

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I thank the participants in the First Annual Conference on EU–U.S. Relations, European Union Center, Georgia Tech, March 1999, where I presented an earlier version of this article. I also thank the participants in the Rational Design project, the editors of IO, and two anonymous reviewers for their feedback. I especially thank Stephan De Spiegeleire, Frank Schimmelfennig, Charles Glaser, Barbara Koremenos, Dan Lindley, Charles Lipson, James Morrow, Duncan Snidal, Robert Pahre, David Pervin, and Peter Rosendorff for their comments and suggestions.

1. Kydd 2000a, b.

2. For the origin of the security community concept, see Deutsch et al. 1957.

3. Gaddis 1998.

4. For the origin of this literature, see Olson and Zeckhauser 1966; and for a survey, see Sandler 1993.

5. See Morrow 1994a; and Smith 1995.

6. See below for the relationship between trust and uncertainty about preferences.

7. For detailed accounts of the process leading up to enlargement, see Eyal 1997; and Goldgeier 1998.

8. Waltz 1979, 127.

9. Walt 1987, 25.

10. See Mearsheimer 1990, 5; and Walt 1997, 171.

11. On the issue of monetary costs, for the optimistic side, see Asmus, Kugler, and Larrabee 1996; and for the pessimists, see Perlmutter and Carpenter 1998; and Rubinstein 1998.

12. Lepgold 1998.

13. Schimmelfennig 1998/99. See also his analysis of EU expansion in Schimmelfennig 2001.

14. Schimmelfennig 1998/99, 211.

15. Ibid., 213–14.

16. NATO 1995.

17. For the beneficial effects of NATO enlargement on Hungarian democracy and Hungarian-Romanian relations, see Kramer 1999, 429–30.

18. See Brown 1996; and Chan 1997.

19. Albright 1998.

20. Schimmelfennig acknowledges this point. Schimmelfennig 1998/99, 230.

21. For an interesting argument that NATO enlargement has not actually accomplished these goals, in particular, has not fostered democracy, see Reiter 2001. Reiter argues that the countries admitted were solid democracies with civilian control of the military before NATO enlargement became a possibility, and hence that NATO enlargement was irrelevant in promoting cooperation in Eastern Europe. Even if one agrees with this point, which I do not fully, my analysis still can explain both the enlargement criteria and the enlargement dilemma, which are a function of policymakers' perception that NATO enlargement would promote democratization and trust building while harming NATO–Russian relations.

22. Deutsch et al. 1957, 5. For a constructivist take on security communities, see Adler and Barnett 1998.

23. Available on the Web at ⟨⟩

24. Garthoff 1997, 10.

25. Gaddis 1998, 145.

26. See Pierre and Trenin 1997; Asmus and Larrabee 1996; Brown 1995; and Mandelbaum 1995.

27. Snyder 1984.

28. Ibid., 477.

29. See Jervis 1976, 62; and Kydd 1997.

30. For a contrary argument that offensive alliances are smaller than defensive ones, see Schweller 1998, 61.

31. See Coleman 1990, 91; Güth and Kliemt 1994; Watson 1999; and Kydd 2000a.

32. See Jervis 1976 and 1978; and Glaser 1994/95 and 1997.

33. Schweller 1998, 15–38.

34. On preventive war, see Copeland 2000, 11–34; on preemptive war, see Van Evera 1999, 35–72.

35. Kydd 2000a,b.

36. This raises a commitment problem. Given that NATO pays a cost (discussed later) to extend a security guarantee, it might be best for them to promise a security guarantee, and then renege on the promise after the allies have moved. I will assume that NATO faces reputational costs sufficient to render such a deceitful strategy unappealing.

37. In reality, of course, there is a much larger set of possible offers. Some states could be given guarantees even if they do not cooperate; others could be denied a guarantee even if they do. The three-part choice is the simplest framework in which we can examine how expansion could be threatening or reassuring, depending on whether it is conditional or unconditional.

38. For quasi-game-theoretic analyses of trust along these lines, see Bennet and Dando 1982; and Plous 1988. Glaser also suggests this strategy for modeling the security dilemma. Glaser 1997.

39. I use the name spiral because this equilibrium is sometimes provocative. Perhaps “conditional spiral” would be a more accurate, if more cumbersome, name.

40. The first and second are not possible for the parameter values illustrated in Figure 2. See the appendix for details.

41. For the debate on NATO and the Baltic states, see Asmus and Nurick 1996; Kamp 1998; and Blank 1998.

42. Morrow 1994b, 170.

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International Organization
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