Emerging Consensus: Results from the Second Wave of Statistical Studies on Civil War Termination

Abstract

This study searches for consensus findings in the burgeoning statistical literature on civil war termination. Several trends are identified: the final outcomes of civil wars are largely dependent on the military situation; the duration of civil wars, by contrast, depends to a great degree on contextual factors such as inter-ethnic relations, the fragmentation of violence, and economic incentives; while compromise settlements reduce the risk of post-war massacres, they take longer to achieve than military victories and are more likely to collapse into renewed warfare. These results also suggest an intervener's dilemma: while external military intervention can lead to compromise and prevent genocide, it also prolongs the killing and may increase the risk of war recurrence. Interveners appear to have more success after wars than during them. Several other puzzles emerge from the statistical results, which call for theoretical development and further qualitative and quantitative analysis.

Notes

 1. Roy Licklider, ‘Early Returns: Results of the First Wave of Statistical Studies of Civil War Termination’, Civil Wars 1/3 (Autumn 1998) pp.121–32.

 2. Frank Vaughan, ‘Win, Lose, and Draw: Civil War and the Determinants of State Concessions’, PhD dissertation, Morgantown, WV: West Virginia U (2006) p.119; Frederic S. Pearson, Marie Olson Lounsbery, Scott Walker and Sonja Mann, ‘Rethinking Models of Civil War Settlement’, International Interactions 32/4 (2006) pp.109–28.

 3. Karl R. DeRouen, Jr. and David Sobek, ‘The Dynamics of Civil War Duration and Outcome’, Journal of Peace Research 41/3 (May 2004) pp.303–20; Dylan Balch-Lindsay, Andrew Enterline and Kyle Joyce, ‘Third Party Intervention and the Civil War Process’, Journal of Peace Research 45/3 (May 2008) pp.345–63; Bidisha Biswas, ‘Managing Discontent: Institutions, Intervention, and Ethnic Conflict’, PhD dissertation, College Park, MD: U of Maryland (2006) p.114; Vaughan (note 2) p.119.

 4. Navin A. Bapat, ‘Insurgency and the Opening of Peace Processes’, Journal of Peace Research 42/6 (Nov. 2005) pp.699–717.

 5. DeRouen and Sobek (note 3) p.312.

 6. Jeffrey Dixon, ‘What Causes Civil Wars? Integrating Quantitative Research Findings’, Working Paper (Tarleton State University, Central Texas 2008) pp.20–21.

 7. Nicholas Sambanis, ‘Partition as a Solution to Ethnic War: An Empirical Critique of the Theoretical Literature’, World Politics 52/4 (July 2000) pp.437–83.

 8. Stephen Edward Gent, ‘The Strategic Dynamics of Military Intervention’, PhD dissertation (Rochester, NY: U of Rochester 2005) p.118.

 9. DeRouen and Sobek (note 3) p.312.

10. DeRouen and Sobek (note 3) p. 312

11. Vaughan (note 2, p.119) included a control variable for Africa in his analysis. Sambanis (note 7, pp.456–57) included a control for continent in his study of partition as a civil war outcome. It was only marginally significant, failing to reach the generally accepted threshold of 95 per cent confidence.

12. Sambanis (note 7) pp.456–57.

13. Biswas (note 3) p.114.

14. DeRouen and Sobek (note 3) p.312; Sambanis (note 7) pp.456–57.

15. Patrick M. Regan, ‘Conditions of Successful Third-Party Intervention in Intrastate Conflicts’, Journal of Conflict Resolution 40/2 (June 1996) pp.336–59; T. David Mason and Patrick J. Fett, ‘How Civil Wars End: A Rational Choice Approach’, Journal of Conflict Resolution 40/4 (Dec. 1996) pp.546–68; Marie Olson and Frederic Pearson, ‘Civil War Characteristics, Mediatiors, and Resolution’, Conflict Resolution Quarterly 19/4 (Summer 2002) pp.421–45; Barbara F. Walter, ‘The Critical Barrier to Civil War Settlement’, International Organization 51/3 (Summer 1997) pp.335–64; Bapat (note 4) p.710; T. David Mason, Joseph P. Weingarten, Jr., and Patrick J. Fett, ‘Win, Lose, or Draw: Predicting the Outcome of Civil Wars’, Political Research Quarterly 52/2 (June 1999) pp.239–68; Isak Svensson, ‘Democracies, Disengagement and Deals: Exploring the Effect of Different Types of Mediators in Internal Armed Conflicts’ in Kaare Strom and Magnus Öberg, Resources, Governance and Civil Conflict (NY: Routledge 2008) pp.227–47; Pearson et al. (note 2) p.123; Vaughan (note 2) p.119.

16. Sambanis (note 7) pp.456–57.

17. Gent (note 8) p.118.

18. Bapat (note 4) p.710.

19. Mason et al. (note 15) p.259.

20. Jeffrey Dixon, ‘Intervention, Capabilities, Costs, and the Outcome of Civil Wars’, PhD dissertation (Houston, TX: Rice U 2001) p.313.

21. Svensson (note 15) p.238; Dixon (‘Intervention, Capabilities, Costs, and the Outcome of Civil Wars’, PhD dissertation (Houston, TX: Rice U 2001)) pp.330–31.

22. Regan (note 15) p.350; Mason and Fett (note 15) p.557; Mason et al. (note 15) p.259; Pearson et al. (note 2) p.123; Vaughan (note 2) p.119; Gent (note 8) p.118.

23. Svensson (note 15) p.238; Sambanis (note 7) pp.456–57.

24. Walter (note 15) p.354.

25. In support are Mason and Fett (note 15) p.259, Walter (note 15) p.354, Pearson et al. (note 2) p.123, and Gent (note 8) p.118. Opposition comes from Olson and Pearson (note 15) p.443. Svensson (note 15) p.238, Vaughan (note 2) p.119, and Mason et al. (note 15) p.259 find no significant relationship.

26. Walter (note 15) p.354; Vaughan (note 2) p.119.

27. Olson and Pearson (note 15) p.443.

28. Mason et al. (note 15) p.259.

29. Walter (note 15) p.354.

30. Svensson (note 15) p.238.

31. Olson and Pearson (note 15) p.443.

32. Regan (note 15) p.350.

33. Mason and Fett (note 15) p.557; Olson and Pearson (note 15) p.443; Mason et al. (note 15) p.259.

34. Biswas (note 3) p.114; Mason et al. (note 15) p.259.

35. Dixon (note 20) pp.308–13.

36. Gent (note 8) p.118.

37. Dixon (note 20) p.313.

38. DeRouen and Sobek (note 3) p.312.

39. Dixon (note 20) p.291.

40. Paul Collier, Anke Hoeffler and Måns Söderbom, ‘On the Duration of Civil War’, Journal of Peace Research 41/3 (May 2004) pp.253–73.

41. DeRouen and Sobek (note 3) p.312; Balch-Lindsay et al. (note 3) p.357; Collier et al. (note 40) pp.260–61; James D. Fearon, ‘Why Do Some Civil Wars Last So Much Longer Than Others?’, Journal of Peace Research 41/3 (May 2004) pp.275–301; Jose G. Montalvo and Marta Reynal-Querol, ‘Ethnic Polarization and the Duration of Civil Wars’, World Bank Policy Research Working Paper 4192, 2007, p.25.

42. Ibrahim Elbadawi and Nicholas Sambanis, ‘External Interventions and the Duration of Civil Wars’, Working Paper at World Bank Development Economic Research Group (2000) p.14.

43. Shanna Kirschner, ‘Fear and Ethnic Civil War Duration’, Working Paper, U of Michigan (2007) p. 17.

44. Montalvo and Reynal-Querol (note 41) p.25.

45. Failing to detect a linear relationship are David E. Cunningham, ‘Veto Players and Civil War Duration’, American Journal of Political Science 50/4 (Oct. 2006) pp.875–92; Kirschner (note 43) p.17; Fearon (note 41) p.285; Montalvo and Reynal-Querol (note 41) p.25.

46. Elbadawi and Sambanis (note 42) p.14; Collier et al. (note 40) pp.260–61.

47. Elbadawi and Sambanis (note 42) p.14.

48. No relationship between mountains and war duration: Halvard Buhaug and Päivi Lujala, ‘Accounting for Scale: Measuring Geography in Quantitative Studies of Civil War’, Political Geography 24/4 (May 2005) pp.399–418; Montalvo and Reynal-Querol (note 41) p.25. Mountains a significant predictor of civil war initiation: James D. Fearon and David D. Laitin, ‘Ethnicity, Insurgency, and Civil War’, American Political Science Review 97/1 (Feb. 2003) pp. 75–90, p.84; Päivi Lujala, Nils Petter Gleditsch and Elisabeth Gilmore, ‘A Diamond Curse? Civil War and a Lootable Resource’, Journal of Conflict Resolution 49/4 (Aug. 2005) pp.538–562; Michael Ross, ‘A Closer Look at Oil, Diamonds, and Civil War’, Annual Review of Political Science 9 (2006) pp.284–85; Randall J. Blimes, ‘The Indirect Effect of Ethnic Heterogeneity on the Likelihood of Civil War Onset’, Journal of Conflict Resolution 50/4 (Aug. 2006) pp.541–42; Susumu Suzuki, ‘Major Arms Imports and the Onset of Civil and Ethnic Wars in the Postcolonial World, 1956–1998: A Preliminary Reassessment’, Social Science Journal 44/1 (Jan. 2007) pp. 99–111, p.106.

49. Buhaug and Lujala (note 48) p.412.

50. On Africa, see DeRouen and Sobek (note 3) p.312; on Eastern Europe, see Fearon (note 41) p.285.

51. No significant association found: Kirshner (note 43) p.17; Fearon (note 41) p.285; Patrick M. Regan and Aysegul Aydin, ‘Diplomacy and Other Forms of Intervention in Civil Wars’, Journal of Conflict Resolution 50/5 (Oct. 2006) pp.736–56; Montalvo and Reynal-Querol (note 41) p.25. Collier (note 40) p.261 found that higher per capita GDP reduces the duration of civil wars, while Balch-Lindsay et al. (note 3, p.357) found that iron and steel production and energy consumption reduced war duration.

52. Balch-Lindsay et al. (note 3) p.357.

53. Collier et al. (note 40) pp.260–61.

54. Fearon (note 41) p.285; Kirschner (note 43) p.17.

55. Buhaug and Lujala (note 48) p.412; Regan and Aydin (note 51) p.748.

56. In agreement: David E. Cunningham, ‘Veto Players and Civil War Duration’, PhD dissertation, San Diego, CA: U of California – San Diego (2006) p.77; Cunningham (note 45) p.886; Fearon (note 41) p.285. In dissent are Seden Akcinaroglu and Elizabeth Radziszewski, ‘Expectations, Rivalries, and Civil War Duration’, International Interactions 31/4 (2005) pp.349–74.

57. Dylan Balch-Lindsay and Andrew Enterline, ‘Killing Time: The World Politics of Civil War Duration, 1820–1992’, International Studies Quarterly 44/4 (Dec. 2000) pp.615–42; Buhaug and Lujala (note 48) p.412 – marginal significance; Akcinaroglu and Radziszewsi (note 56) p.366; Regan and Aydin (note 51) p.748; Patrick M. Regan, ‘Third-Party Interventions and the Duration of Intrastate Conflicts’, Journal of Conflict Resolution 46/1 (Feb. 2002) pp.55–73; Elbadawi and Sambanis (note 42) p.14; Fearon (note 41) p.285; Curtis Meek, ‘A Competing Risks Model of Civil War Duration, 1944–1994’, Paper presented at Peace Science Society annual meeting, Ann Arbor, MI (Oct. 1999) p.24 (with respect to time to settlement only).

58. Kirschner (note 43) p.17.

59. Dixon (note 20) pp.361–63; Balch-Lindsay and Enterline (note 57) p.630.

60. Regan and Aydin (note 51) p.748.

61. Cunningham (note 56) p.77; Cunningham (note 45) p.886.

62. Respectively, these are Meek (note 57) p.24; Regan and Aydin (note 51) p.748; Regan, ‘Third-Party’ (note 57) p.69; Fearon (note 41) p.285.

63. Balch-Lidsay and Enterline (note 57) p.630.

64. Kirschner (note 43) p.17.

65. Regan and Aydin (note 51) p.748.

66. Regan, ‘Third-Party’ (note 57) p.69.

67. Regan and Aydin (note 51) p.748; Regan, ‘Third-Party’ (note 57) p.69.

68. Elbadawi and Sambanis (note 42) p.14; Akcinaroglu and Radziszewsi (note 56) p.366.

69. Regan, ‘Third-Party’ (note 57) p.69; Balch-Lindsay and Enterline (note 57) p.630.

70. For a thorough summary, see Paul Collier, Lani Elliott, Håvard Hegre, Anke Hoeffler, Marta Reynal-Querol and Nicholas Sambanis, Breaking the Conflict Trap: Civil War and Development Policy (Washington, DC: World Bank and Oxford UP 2003), Chapters 1–2. For more details of the effects on public health, see Hazem Adam Ghobarah, Paul Huth and Bruce Russett, ‘Civil Wars Kill and Maim People – Long after the Shooting Stops’, American Political Science Review 97/2 (May 2003) pp.189–202.

71. Reşat Bayer and Matthew C. Rupert, ‘Effects of Civil Wars on International Trade, 1950–92’, Journal of Peace Research 41/6 (Nov. 2004) pp.699–713.

72. Seonjou Kang and James Meernik, ‘Civil War Destruction and the Prospects for Economic Growth’, Journal of Politics 67/1 (Feb. 2005) pp.88–109.

73. Thomas Chapman and Philip G. Roeder, ‘Partition as a Solution to Wars of Nationalism: The Importance of Institutions’, American Political Science Review 101/4 (Nov. 2007) pp.677–91; Matthew Kohler, ‘What Can the Collective Action Problem Tell Us About the Recurrence of Civil War and the Long-Term Stability of a Country?’, MS thesis, U of North Texas (2005) pp.52–53. For dissenting views, see Sambanis (note 7) pp.456–57 (no significant relationship found) and Barbara F. Walter, ‘Does Conflict Beget Conflict? Explaining Recurring Civil War’, Journal of Peace Research 41/3 (May 2004) pp.371–88 (partition found to increase risk of renewed war).

74. Virginia Page Fortna, ‘Inside and Out: Peacekeeping and the Duration of Peace after Civil and Interstate Wars’, International Studies Review 5/4 (2003) pp.97–114; Virginia Page Fortna, ‘Does Peacekeeping Keep Peace? International Intervention and the Duration of Peace after Civil War’, International Studies Quarterly 48/2 (Jun. 2004) pp.269–92; Monica Toft, ‘Peace through Security: Making Negotiated Settlements Stick’, REGIS Working Paper No. 23 (Nov. 2006) p.16.

75. Bumba Mukherjee, ‘Why Political Power-Sharing Agreements Lead to Enduring Peaceful Resolution of Some Civil Wars, But Not Others?’, International Studies Quarterly 50/2 (Jun. 2006) pp.479–504.

76. Walter (note 73), p.381; T. David Mason, Mehmet Gurses, Patrick Brandt and Jason Michael Quinn, ‘When and Why Civil Wars Recur: Conditions for a Durable Peace After Civil Wars?’, Working Paper, p.26. Another study did find that war recurrence was less likely after victories, although the significance was marginal: Jason Michael Quinn, T. David Mason and Mehmet Gurses, ‘Sustaining the Peace: Determinants of Civil War Recurrence’, International Interactions 33/2 (2007) pp.167–93.

77. Caroline Hartzell, ‘Civil Wars, Military Victories, and Enduring Peace: A Test of the Wagner Hypothesis’, Paper presented at the annual meeting of the Midwest Political Science Association (Apr. 2004) p.10.

78. Caroline Hartzell, Matthew Hodie and Donald Rothchild, ‘Stabilizing the Peace after Civil War: An Investigation of Some Key Variables’, International Organization 55/1 (Winter 2001) pp.183–208; Matthew Hodie and Caroline Hartzell, ‘Power Sharing in Peace Settlements: Initiating the Transition from Civil War’ in Philip Roeder and Donald Rothchild, Sustainable Peace: Power and Democracy after Civil Wars (Ithaca, NY: Cornell UP 2005) pp.83–106; Michael W. Doyle and Nicholas Sambanis, ‘International Peacebuilding: A Theoretical and Quantitative Analysis’ American Political Science Review 94/4 (Dec. 2000) pp.779–801; Quinn et al. (note 76) p.184. Note that Hoddie and Hartzell limit their analyses to negotiated settlements only, so it is unclear whether civil war recurrence is more likely after a properly structured settlement (as opposed to a mere cease-fire) than after a military victory.

79. Dixon (note 20) p.291.

80. Mehmet Gurses and T. David Mason, ‘Democracy Out of Anarchy: The Prospects for Post-Civil-War Democracy’, Social Science Quarterly 89/2 (Jun. 2008) pp.315–36.

81. Fortna, ‘Inside and Out’ (note 74) p.107.

82. I. William Zartman, ‘Dynamics and Constraints in Negotiations in Internal Conflicts’ in I. William Zartman, Elusive Peace: Negotiating an End to Civil Wars (Washington DC: Brookings Institution 1995) p.7.

83. Sarah D. Eberle, Christian W. Martin and Gerald Schneider, ‘The Spillovers of Globalization and Civil War: Opposite or Parallel Sources of Violence Domestic Conflict?’, Working Paper (2003); Idean Salehyan, ‘Rebels Without Borders: State Boundaries, Transnational Opposition, and Civil Conflict’, PhD dissertation, U of California, San Diego (2006); Tanja Ellingsen, ‘Colorful Community or Ethnic Witches’ Brew? Multiethnicity and Domestic Conflict During and After the Cold War’, Journal of Conflict Resolution 44/2 (Apr. 2000) pp.228–249. Marginal significance: James D. Fearon, ‘Primary Commodity Exports and Civil War’, Journal of Conflict Resolution 49/4 (Aug. 2005) pp.483–507; Paul Collier and Anke Hoeffler, ‘The Political Economy of Secession’, World Bank Working Paper (2002) p.32; Paul Collier and Anke Hoeffler, ‘Greed and Grievance in Civil War’, Oxford Economic Papers 56/4 (Oct. 2004) pp.563–95.

84. Dixon (note 20) p.291.

85. Scott Gates and Håvard Strand, ‘Modeling the Duration of Civil Wars: Measurement and Estimation Issues’, Paper presented at the meeting of the Standing Group on International Relations (Sept. 2004) pp.22–26.

86. Nicholas Sambanis, ‘What Is Civil War? Conceptual and Empirical Complexities of an Operational Definition’, Journal of Conflict Resolution 48/6 (Dec. 2004) pp.832–34.

87. Sambanis (note 86) pp.838–53. This description refers to the results, excluding constants, in Tables 2, 4, 6, and 7. Table 8 replicates the sign-switch on this variable.

88. Håvard Hegre and Nicholas Sambanis, ‘Sensitivity Analysis of Empirical Results on Civil War Onset’, Journal of Conflict Resolution 50/4 (Aug. 2006) p.529.

89. Gates and Strand (note 85) p.4.

90. Gates and Strand (note 85) p.27.

91. Licklider (note 1) p.121.