Interstate peacekeeping: Causal mechanisms and empirical effects

World Politics

Volumn 56, Issue 4, 2004, Pages 481-519

  Fortna, Virginia Page ^a  

^a Och Spine at New York Presbyterian Hospitals   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CIVIL WAR; CONFLICT MANAGEMENT; PEACEKEEPING;

EID: 17944366365     PISSN: 00438871     EISSN: None     Source Type: Journal    
DOI: 10.1353/wp.2005.0004     Document Type: Review

References (141)

1. Although this is usually done by the UN, it is sometimes done by regional organizations or by an ad hoc group.
2. A. B. Fetherston, Towards a Theory of United Nations Peacekeeping (New York: St. Martin's Press, 1994).
3. On the disconnect between peacekeeping practice and theory, see Stephen Ryan, "The Theory of Conflict Resolution and the Practice of Peacekeeping," in Edward Moxon-Browne, ed., A Future for Peacekeeping? (New York: St. Martin's Press, 1998).
4. Perhaps the most theoretical works are the classics: Alan James, The Politics of Peace-keeping (New York: Praeger, 1969);
5. and Indar Jit Rikhye, The Theory and Practice of Peacekeeping (London: C. Hurst and Company, 1984).
6. Duane Bratt, "Assessing the Success of UN Peacekeeping Operations," International Peacekeeping 3 (Winter 1996);
7. William J. Durch, ed., The Evolution of UN Peacekeeping (New York: St. Martin's Press, 1993);
8. William J. Durch, ed., UN Peacekeeping, American Politics and the Uncivil Wars of the 1990s (New York: St. Martin's Press, 1996);
9. Lise Morjé Howard, "Learning to Keep the Peace? United Nations Multidimensional Peacekeeping in Civil Wars" (Ph.D. diss., University of California, Berkeley, 2001);
10. Jean Krasno, Bradd C. Hayes, and Donald C. F. Daniel, eds., Leveraging to Success in United Nations Peace Operations (Westport, Conn.: Praeger, 2003);
11. John Mackinlay, The Peacekeepers: An Assessment of Peacekeeping Operations at the Arab-Israeli Interface (London: Unwin Hyman, 1989).
12. See, for example, Michael W. Doyle and Nicholas Sambanis, "International Peacebuilding: A Theoretical and Quantitative Analysis," American Political Science Review 94 (December 2000);
13. Amitabh Dubey, "Domestic Institutions and the Duration of Civil War Settlements" (Paper presented at the annual meeting of the International Studies Association, New Orleans, March 24-27, 2002);
14. Virginia Page Fortna, "Does Peacekeeping Keep Peace? International Intervention and the Duration of Peace after Civil War," International Studies Quarterly 48 (June 2004);
15. Caroline Hartzell, Mathew Hoddie, and Donald Rothchild, "Stabilizing the Peace after Civil War," International Organization 55 (Winter 2001).
16. The conventional wisdom is that peacekeeping is less effective in internal conflicts than in its traditional setting between sovereign states. For a preliminary comparison of peacekeeping's effects in the two types of war, see Virginia Page Fortna, "Inside and Out: Peacekeeping and the Duration of Peace after Civil and Interstate Wars," International Studies Review 5 (December 2003).
17. For example, Ernst B. Haas, Robert L. Butterworth, and Joseph S. Nye, Conflict Management by International Organizations (Morristown, N.J.: General Learning Press, 1972).
18. Ernst B. Haas, Why We Still Need the United Nations: The Collective Management of International Conflict, 1945-1985 (Berkeley: Institute of International Studies, University of California, Berkeley, 1986).
19. Jonathan Wilkenfeld and Michael Brecher, "International Crises, 1945-1975: The UN Dimension," International Studies Quarterly 28 (March 1984).
20. Paul F. Diehl, Jennifer Reifschneider, and Paul R. Hensel, "UN Intervention and Recurring Conflict," International Organization 50 (Autumn 1996).
21. The results of recent studies on civil wars are similarly contradictory. Doyle and Sambanis (fn. 5) find that some forms of peacekeeping lead to "peacebuilding success"; Dubey (fn. 5) finds that peacekeeping has no significant effect on the duration of peace; while Fortna (fn. 5) finds peacekeeping to have a significant positive impact in the post-cold war era.
22. On war termination see, for example, Barbara Walter, "The Critical Barrier to Civil War Settlement," International Organization 51 (Summer 1997);
23. idem, Committing to Peace: The Successful Settlement of Civil Wars (Princeton: Princeton University Press, 2001);
24. H. E. Goemans, War and Punishment: The Causes of War Termination and the First World War (Princeton: Princeton University Press, 2000).
25. On the duration of peace, see Suzanne Werner, "The Precarious Nature of Peace: Resolving the Issues, Enforcing the Settlement and Renegotiating the Terms," American Journal of Political Science 43 (July 1999);
26. Virginia Page Fortna, "Scraps of Paper? Agreements and the Durability of Peace," International Organization 57 (Spring 2003);
27. idem, Peace Time: Cease-Fire Agreements and the Durability of Peace (Princeton: Princeton University Press, 2004).
28. For an analysis of third-party mediation and security guarantees after interstate wars, see Fortna (fn. 12, 2004).
29. This notion is tested directly below. Werner's study (fn. 12) covers a much longer time period (1816-1992). However, peacekeeping was "invented" only after World War II, making the time period examined here a better test of its effects.
30. Thomas G. Weiss, David P. Forsythe, and Roger A. Coate, The United Nations and Changing World Politics, 2nd ed. (Boulder, Colo.: Westview Press, 1997), 53.
31. Paul F. Diehl, International Peacekeeping (Baltimore: Johns Hopkins University Press, 1993), 9;
32. Durch (fn. 4, 1993), 4.
33. Monitoring missions typically range in size from a few dozen observers to several hundred; they are unarmed (though observers are military personnel). Peacekeeping forces are lightly armed for "defensive purposes." In interstate cases, these missions have ranged from about twelve hundred to thirteen thousand troops. I use the general term peacekeeping to refer to both types of missions; I use the terms monitoring and peacekeeping forces or armed peacekeepers to distinguish between them.
34. Diehl (fn. 16), 10;
35. James (fn. 3);
36. Alan James, Peacekeeping in International Politics (New York: St. Martin's Press, 1990).
37. For a fuller discussion of these difficulties and mechanisms that can be used to overcome them, see Fortna (fn. 12, 2004).
38. It is rare for states to be drawn into war purely by accident; it requires deliberate action to decide to retaliate. But the familiar dynamic of the security dilemma suggests how accidents might set off an escalatory cycle of clashes that can lead back to full-scale war. Robert Jervis, Perception and Misperception in International Politics (Princeton: Princeton University Press, 1976).
39. Note, however, that some might argue just the opposite, that peace should be most stable in the immediate aftermath of war. According to the informational perspective on war, it is states' inability credibly to reveal their intentions and capabilities that leads to war. James D. Fearon, "Rationalist Explanations for War," International Organization 49 (Summer 1995). The fighting of the war itself, however, credibly reveals this information. The danger of renewed war should therefore be lowest when one has just been fought. This argument does not hold up well empirically, however. Rather, peace has been found to be most precarious just after fighting ends, becoming more stable over time.
40. Fortna (fn. 12, 2004), 171-72;
41. Warner (fn. 12) 927.
42. The development of more robust "peace enforcement" missions in civil conflicts, increasingly common after the mid-1990s (for example, the NATO mission in Bosnia or the UN mission in Sierra Leone) represents a significant departure from traditional peacekeeping and may enhance the deterrent effects of peacekeeping.
43. Even for states with a powerful ally in the Security Council willing to veto any UN sanctions, blatant violations can temper that ally's diplomatic support.
44. Direct effects of monitoring may be more important in civil conflicts, particularly for rebel groups without sophisticated intelligence-gathering capability.
45. To be exact, of the forty-eight cease-fires analyzed in this article, peacekeepers are present in thirty-four. Of these, war resumes in eighteen, or 53 percent. Of the fourteen with no peacekeepers, war resumes in only three, or 21 percent.
46. Luttwak's more general argument is similar-that intervening to set up and maintain a cease-fire too early, before war "burns itself out," only postpones the war-induced exhaustion that will lead to accommodation and stable peace; Edward N. Luttwak, "Give War a Chance," Foreign Affairs 78 (July-August 1999).
47. For a related argument, see George W. Downs, David M. Rocke, and Peter N. Barsoom, "Is the Good News about Compliance Good News about Cooperation?" International Organization 50 (Summer 1996).
48. Stuart A. Bremer, "Dangerous Dyads: Conditions Affecting the Likelihood of Interstate War, 1816-1965," Journal of Conflict Resolution 36 (June 1992);
49. Fortna (fn. 12, 2004);
50. Scott Sigmund Gartner and Randolph M. Siverson, "War Expansion and War Outcomes," Journal of Conflict Resolution 40 (March 1996);
51. Gary Goertz and Paul F. Diehl, "The Empirical Importance of Enduring Rivalries," International Interactions 18, no. 2 (1992);
52. idem, "Enduring Rivalries: Theoretical Constructs and Empirical Patterns," International Studies Quarterly 37 (June 1993);
53. Paul R. Hensel, "One Thing Leads to Another: Recurrent Militarized Disputes in Latin America, 1816-1986," Journal of Peace Research 31 (August 1994);
54. idem, "The Evolution of Interstate Rivalry" (Ph.D. diss., University of Illinois, 1996);
55. idem, "Territory: Theory and Evidence on Geography and Conflict," in John A. Vasquez, ed., What Do We Know about War (Lanham, Md: Rowman and Littlefield, 2000);
56. Paul K. Huth, "Territory: Why Are Territorial Disputes between States a Central Cause of International Conflict?" in Vasquez, What Do We Know about War?;
57. Alexander Kozhemiakin, "Outcomes of War and the Durability of Peace Settlements" (Manuscript, Olin Institute, Harvard University, 1994);
58. Zeev Maoz, "Peace by Empire? Conflict Outcomes and International Stability, 1816-1976," Journal of Peace Research 21 (September 1984);
59. Douglas M. Stinnett and Paul F. Diehl, "The Path(s) to Rivalry: Behavioral and Structural Explanations of Rivalry Development," Journal of Politics 63 (August 2001);
60. Werner (fn. 12).
61. As noted above, this study builds on my previous work (see fn. 12), examining in greater depth one of a number of mechanisms used to maintain peace. Others of these mechanisms, particularly demilitarized zones and arms control measures, are somewhat correlated with peacekeeping. Because these other mechanisms are not causally prior to peacekeeping, I do not include them in the analysis presented below, but I have checked whether the results hold up when these correlated mechanisms are controlled for. They do. The hazard ratios remain the same, although, as we would expect when multicollinearity is introduced, the standard errors become somewhat larger, in some cases missing the conventional 0.05 standard for significance.
62. For a similar approach to evaluating the effectiveness of peacekeeping in the context of civil wars, see Fortna (fn. 5).
63. For more detailed information on the Cease-Fires Dataset, see Fortna (fn. 12, 2004). The data are available at http://www.columbia.edu/~vpf4/ research.htm.
64. The time periods run consecutively from the cease-fire to the outbreak of another war, or until the data are censored (see fn. 37) in 1998.
65. J. David Singer and Melvin Small, "Correlates of War Project: International and Civil War Data, 1816-1992" (ICPSR 9905, 1994);
66. Allan C. Stam, Win, Lose, or Draw: Domestic Politics and the Crucible of War (Ann Arbor: University of Michigan Press, 1996);
67. Werner (fn. 12).
68. Werner (fn. 12).
69. Michael Brecher and Jonathan Wilkenfeld, "International Crisis Behavior Project, 1918-1988" (ICPSR 9286, 1992).
70. Note that the failure of peace between India and Pakistan in 1999 with the Kargil War, and between the U.S. and Iraq in 2003 occur after the data are censored.
71. Duration or survival models such as the Weibull have several desirable properties. They do not require an arbitrary specification of "successful" peace (such as a five-year cutoff) but can treat the stability of peace as a continuous variable. They are also adept at handling censored data, in which observation ends before peace has failed. While we know, for example, that the Korean armistice has held to date, we do not know for certain that it will continue to hold in the future. Duration models incorporate this uncertainty into their estimations. For a technical discussion, see William H. Greene, Econometric Analysis (New York: MacMillan, 1993).
72. Janet M. Box-Steffensmeier and Bradford S. Jones, "Time is of the Essence: Event History Models in Political Science," American Journal of Political Science 41 (October 1997). The results for peacekeeping are, if anything, stronger in the Cox model, but analyzing goodness of fit by plotting the empirical Aalen-Nelson cumulative hazard function against Cox-Snell residuals suggests that the Weibull model fits the data better than the Cox model.
73. For work in this direction, see James Raymond Vreeland, "Selection and Survival" (Manuscript, Department of Political Science, Yale University, 2002). His solution is not applicable here because the assignment of peacekeeping is static, not dynamic; that is, it is determined at the beginning of a spell of peace not at independent intervals over the spell of peace.
74. See also Frederick J. Boehmke, Daniel Morey, and Megan Shannon, "Selection Bias and Continuous- Time Duration Models: Consequences and a Proposed Solution" (Manuscript, University of Iowa, July 2004).
75. In other words, the relationship shown holds constant the fact that neither side has been eliminated or has had a new government imposed on it. Because there is no variation in peacekeeping in the few cases with such extreme military outcomes, this variable cannot be included in the multinomial logit analysis.
76. 2) = 0.02).
77. Werner (fn. 12). It is not clear, however, whether changing capabilities affect the resumption of war or whether the resumption of war (or its anticipation) changes measures of material capabilities. See Fortna (fn. 12, 2003), 353.
78. See Fortna (fn. 12, 2003), 353.
79. These peacekeeping measures include both newly deployed missions and those left over from an earlier conflict. The results are the same or stronger if the measure including only new missions is used.
80. As noted above, war outcomes fall into three categories: ties, which are shown here to have the highest risk of resumption; decisive victories short of elimination or regime change, which is the omitted category in Tables 3 and 4; and elimination or foreign-imposed regime change, shown to be the most stable.
81. For a brief summary of the war, see Jacob Bercovitch and Robert Jackson, International Conflict: A Chronological Encyclopedia of Conflicts and Their Management, 1945-1995 (Washington, D.C.: Congressional Quarterly, 1997), 148-49.
82. I. William Zartman, Ripe for Resolution: Conflict and Intervention in Africa (New York: Oxford University Press, 1989), 104-5.
83. Bercovitch and Jackson (fn. 45), 230-31.
84. In 1988 Ethiopia and Somalia signed a peace agreement pledging among other things to stop aiding rebel armies fighting the other. Jeffrey A. Lefebvre, Arms for the Horn: US Security Policy in Ethiopia and Somalia, 1953-1991 (Pittsburgh: University of Pittsburgh Press, 1991);
85. Samuel M. Makinda, "Security in the Horn of Africa," Adelphi Papers 269 (Summer 1992). Somalia was engulfed in its own civil war soon after, and its claim to the Ogaden has lain dormant.
86. For an overview of the repeated rounds of fighting between China and Vietnam, see Bercovitch and Jackson (fn. 45), 188-89, 212, 216-17. The interstate conflict eventually wound down with the resolution of Cambodia's civil war in 1991.
87. The short-lived cease-fire reached between Azerbaijan and Armenia in 1992 provides another example. An Iranian-brokered cease-fire halted the fighting over Nagorno-Karabakh in March 1992, but the war resumed only three weeks later. The war ended in 1994 only after Armenia had occupied Nagorno-Karabakh and almost 20 percent of the rest of Azerbaijan. Patricia Carley, "Nagorno-Karabakh: Searching for a Solution," in USIP Roundtable Report (Washington, D.C.: United States Institute of Peace, 1998).
88. By contrast, most peacekeeping missions in civil wars have included at least some armed troops, often along with sizable civilian components.
89. The UN-flagged force that fought during the Korean War is not considered a peacekeeping mission here; the Neutral Nations Supervisory Committee deployed after the war is. It consisted of monitors from Sweden, Switzerland, Poland, and Czechoslovakia operating in twenty teams of at least four observers. Agreement between the Commander-in-Chief, United Nations Command, on the one hand, and the Supreme Commander of the Korean People's Army and the Commander of the Chinese People's Volunteers, on the other hand, Concerning a Military Armistice in Korea (Panmunjom, Korea, July 27, 1953).
90. The other cases in this category provide less insight. While monitors in Korea may have helped stabilize the armistice to some extent, nuclear deterrence makes the case overdetermined. Monitors deployed in Vietnam in 1973 were quickly overtaken by events. The UN Iraq-Kuwait Observation Mission (UNIKOM) deployed at the end of the Gulf War is an unusual case in that, having sanctioned the war against Iraq, the UN could not claim impartiality as observers. This mission was later converted into an armed peacekeeping mission. The UN Iran-Iraq Military Observer Group (UNIIMOG) operated much like UNTSO and UNMOGIP. UNIIMOG is credited with keeping a number of serious skirmishes from escalating out of control in the first months of the cease-fire after the Iran-Iraq War and with helping to keep peace until Iraq's more pressing security concerns in the Gulf War prompted reconciliation with Iran in January 1991. Brian D. Smith, "United Nations Iran-Iraq Military Observer Group," in William Durch, ed., The Evolution of UN Peacekeeping (New York: St. Martin's Press, 1993);
91. see also United Nations, The Blue Helmets: A Review of United Nations Peace-Keeping, 3rd ed. (New York: United Nations, 1996), 669-78.
92. Sydney D. Bailey, Four Arab-Israeli Wars and the Peace Process (London: Macmillan, 1990).
93. Russell Brines, The Indo-Pakistani Conflict (London: Pall Mall Press, 1968), 239, 320.
94. For detailed accounts of UNTSO and its operations, see Pablo de Azcarate, Mission in Palestine (Washington, D.C.: Middle East Institute, 1966);
95. David Brook, Preface to Peace: The United Nations and the Arab-Israeli Armistice System (Washington, D.C.: Public Affairs Press, 1964);
96. General Odd Bull, War and Peace in the Middle East: The Experiences and Views of a U.N. Observer (London: Leo Cooper, 1976);
97. Lt. General E. L. M. Burns, Between Arab and Israeli, 2nd ed. (Beirut: Institute for Palestine Studies, 1969);
98. E. H. Hutchison, Violent Truce (New York: Devin-Adair, 1956);
99. Lucien Lee Kinsolving, "The Israeli-Syrian Demilitarized Zones: The UN Security Council Record" (Master's thesis, American University, 1967);
100. Nathan A. Pelcovits, The Long Armistice: UN Peacekeeping and the Arab-Israeli Conflict, 1948-1960 (Boulder, Colo.: Westview Press, 1993).
101. For specific examples, see N. Bar-Yaacov, The Israel-Syrian Armistice: Problems of Implementation, 1949-1966 (Jerusalem: Magnes Press, Hebrew University, 1967);
102. Fred J. Khouri, "Friction and Conflict on the Israeli-Syrian Front," Middle East Journal 17 (Winter-Spring 1963), 21.
103. Azcarate (fn. 55), 100;
104. Bull (fn.55), 54, 62;
105. Burns (fn. 55), 27.
106. Pauline Dawson, The Peacekeepers of Kashmir (London: Hurst and Company, 1994), 304.
107. Brines (fn. 54);
108. Joseph Kortel, Danger in Kashmir (Princeton: University, 1954);
109. Alastair Lamb, The Kashmir Problem (New York: Praeger, 1966);
110. idem, Kashmir: A Disputed Legacy, 1846-1990 (Hertingfordbury: Roxford Books, 1991).
111. United Nations (fn. 52), 138-39.
112. India's wariness of UN involvement reflected reluctance to hold the plebiscite promised in Kashmir in 1949 as part of UN Commission for India and Pakistan resolutions, as well as a desire to settle issues with Pakistan bilaterally. It also stemmed in large part from the sovereignty concerns of a relatively new state. As is often the case, states that have newly won independence from colonial powers are reluctant to allow international forces back on their soil, thus constraining UN involvement.
113. General (ret.) Jehangir Karamat of the Pakistan Army (Presentation at CISAC, Stanford University, May 19, 1999).
114. United Nations, Security Council, Report by the Secretary-General on the Current Situation in Kashmir with Particular Reference to the Cease-Fire Agreement, the Cease-Fire Line and the Functioning of UNMOGIP (S/6651), September 3, 1965, 7.
115. Adam Roberts, "The Crisis in UN Peacekeeping," in Chester A. Crocker, Fen Osler Hampson, and Pamela Aall, eds., Managing Global Chaos (Washington, D.C.: U.S. Institute of Peace, 1996).
116. During the tenure of Secretary-General Boutros Boutros-Ghali, the UN became less reluctant to condemn belligerents;
117. Howard (fn. 4). This trend has continued under Kofi Annan.
118. See, for example, United Nations, General Assembly and Security Council, Report of the Panel on United Nations Peace Operations (the Brahimi Report) (A/55/305-S/2000/809), August 21, 2000.
119. The OAS secretary-general, Galo Plaza, had been involved in UN peacekeeping in Lebanon and Cyprus and was determined to avoid getting "locked in" and having peacekeepers stay for years. He insisted that "the parties themselves must take over full responsibility." Quoted in David W. Wainhouse, International Peacekeeping at the Crossroads (Baltimore: Johns Hopkins University Press, 1973), 590.
120. Mary Jeanne Reid Martz, The Central American Soccer War: Historical Patterns and Internal Dynamics of OAS Settlement Procedures (Athens: Ohio University Center for International Studies, 1978), 73-80.
121. This last case falls outside the temporal scope of the quantitative analysis above. Adding it, however, would strengthen the finding that peace is more likely to last when peacekeepers are present.
122. Britain and France agreed to withdraw as soon as a UN force was in position to ensure that hostilities would not resume;
123. United Nations (fn. 52), 45.
124. Bailey (fn. 53).
125. Up to this point, Israel had viewed aggressive posturing in Egypt as merely political maneuvering; Fred J. Khouri, The Arab-Israeli Dilemma, 3rd ed. (Syracuse, N.Y.: Syracuse University Press, 1985), 245-48.
126. United Nations (fn. 52), 54.
127. United Nations (fn. 52), 53.
128. UNTSO observers were not even able to tell which side started the Yom Kippur War. Bailey (fn. 53), 308;
129. Moshe Ma'oz, Syria and Israel: From War to Peacemaking (Oxford: Clarendon Press, 1995), 99.
130. Opposition from Arab states and the Soviets to the bilateral Egyptian-Israeli peace process precluded any continued UN peacekeeping role.
131. Israel, previously opposed to strong peacekeeping forces, pushed for a large force of at least three thousand troops. Syria, by contrast, was concerned about infringements on its sovereignty and wanted a nonmilitary operation of only a few hundred monitors. They settled on 1,250 UN troops. The issue was touchy enough politically that even the name of the operation was an issue, with both "observer" and "force" in the title as a compromise. Henry Kissinger, Years of Upheaval (Boston: Little, Brown, 1982), 1044, 1094.
132. Mona Ghali, "United Nations Disengagement Observer Force," in William J. Durch, ed., The Evolution of UN Peacekeeping (New York: St Martin's, 1993).
133. A request by either side that the UN mission depart would be seen as a distinctly hostile act by the other side.
134. The impotence of peacekeepers in the face of determined aggression is perhaps best exemplified by the case of Lebanon in 1982, when the role of the peacekeepers was reduced to counting Israeli tanks as they rolled by.
135. Brines (fn. 54), 310.
136. Israel has always been concerned with U.S. opinion, often waiting for a green, or at least a yellow, light from Washington before acting militarily. Khouri (fin. 70), 244;
137. Ma'oz (fn. 73), 100-101. India also delayed military action against Pakistan in 1971 because of concerns about international reaction to a precipitous attack;
138. Sumit Ganguly, The Origins of War in South Asia: Indo-Pakistani Conflicts since 1947 (Boulder, Colo.: Westview Press, 1986), 120.
139. This is true both of scholars generally inclined to see the peacekeeping as efficacious, such as Wainhouse (fn. 65), chap. 3, and of a skeptic on the UN's role like Brines (fn. 54).
140. E. D. Doyle, "Eyewitness: Verification in the Sinai," Journal of International Peacekeeping 1 (Autumn 1994);
141. Nathan A. Pelcovits, Peacekeeping on Arab-Israeli Fronts: Lessons from the Sinai and Lebanon (Boulder, Colo.: Westview Press, 1984).