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Why foreign military interventions prolong civil wars: lessons from Yemen

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Abstract

Foreign military interventions are correlated with longer civil wars, yet existing explanations for this association remain inadequate. One influential argument claims that outside states prolong internal warfare by introducing objectives that are extraneous to the conflict at hand. A more compelling extension of this argument is that intervening states forge alliances with local combatants, and contention among these local combatants creates friction among intervening states and opens the door to additional combatants. Such dynamics lengthened the civil war in Yemen that erupted in 2012–13. Exploring the shifting patterns of antagonism and alignment that accompanied intervention in this particular case improves our general understanding of the mechanisms that increase the duration of internal warfare.

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Notes

  1. Contrary findings are reported by Balch-Lindsay, Enterline and Joyce (2008, 356–357).

  2. See also Desrosiers and Vucetic (2018).

  3. Thanks to an anonymous reviewer for raising this possibility.

  4. Thanks again to an anonymous reviewer for this intriguing suggestion.

  5. President Hadi rescinded his resignation as soon as he decamped to Aden in early February.

References

  • Abdu, M. 2018. Yemen's Aden faces escalating conflict after attack by secessionists. Xinhua News Agency. 19 August

  • Abdul-Ahad, G. 2016. The City Where War is the Best Employer. The Guardian. 18 February.

  • Abdullah, J. 2015. Geopolitical context of operation decisive storm and GCC States’ attitudes toward it. Doha: Al Jazeera Centre for Studies.

    Google Scholar 

  • Abu-Bader, S., and E. Ianchovichina. 2019. Polarization, foreign military intervention and civil conflict. Journal of Development Economics 141 (5): 1–32.

    Google Scholar 

  • Agence France Presse. 2016a. Gunmen Kill Police Colonel, Four Others in Yemen's Aden. 24 January.

  • Agence France Presse. 2016b. Yemen Police Chief Wounded in Aden Suicide Bombing. 3 February.

  • Agence France Presse. 2017a. South Yemen Leaders Defy Government with Local Council. 11 May.

  • Agence France Presse. 2017b. Southern Yemenis Stage Independence Rally. 21 May.

  • Agence France Presse. 2017c. Southern Yemenis Rally for Independence. 7 July.

  • Al Qalisi, M. 2017. Massive Protests in Aden to Support Separate Rule for South Yemen. The National. 14 July.

  • Al Wasmi, N. and A. Mahmood. 2017. Sanaa "Paralysed" in Rebel-Alliance Clashes. The National. 3 December.

  • al-Akhbar. 2016a. Southerners to Announce ‘Disengagement’ Tomorrow. 20 May.

  • al-Akhbar. 2016b. Hadramawt to Be Snatched Away from the South. 9 December.

  • al-Akhbar. 2018a. Tariq Salih is Rejected in the South. 17 January.

  • al-Akhbar. 2018b. Tariq Salih on the Coastal Front. 18 April.

  • al-Akhbar. 2018c. On the Clashes between the Pro-Alliance Parties in Ta'izz. 27 April.

  • al-Akhbar. 2018d. Saudi Arabia ‘Swallows Emirati Blade’ in Hadramawt: Until When? 28 April.

  • al-Akhbar. 2018e. The Failure of al-Hudaidah Offensive Renews Differences at the Level of the Alliance Front. 5 July.

  • al-Dawsari, N. 2018. Our Common Enemy: Ambiguous Ties between al-Qaeda and Yemen's Tribes. Beirut: Carnegie Middle East Center

  • al-Falahi, A. 2015. Islamic State Extends Its Tentacles into Yemen. al-monitor.com. 30 November.

  • al-Falahi, A. 2016. Why Yemen May Not be Heading for a Split. al-monitor.com. 10 February.

  • al-Hammadi, K. 2016. Yemen: Salih Activates al-Qaidah Card in South. al-Quds al-'Arabi. 3 February.

  • al-Hammadi, K. 2017a. Aden's Ousted Governor Announces Formation of ‘Transitional Council’ Opposed to Legitimate Authority. al-Quds al-'Arabi. 12 May.

  • al-Hammadi, K. 2017b. Yemen: Southern Cause Returns to Forefront of Political Scene. al-Quds al-'Arabi. 7 July.

  • al-Hammadi, K. 2018a. Yemen: Hadi Orders End of Emirati Troops' Control Over Territories in Suqutra Island. al-Quds al-'Arabi. 7 February.

  • al-Hammadi, K. 2018b. Yemen: Political Components Announce Formation of Unionist "Southern National Coalition". al-Quds al-'Arabi. 3 May.

  • al-Hammadi, K. 2018c. Yemen: Large Emirati Force Officially Occupies Suqutra Island. al-Quds al-'Arabi. 4 May.

  • al-Hammadi, K. 2018d. Yemen: Hadi Facing "Critical Challenges" in Aden. al-Quds al-'Arabi. 25 July.

  • al-Hammadi, K. 2018e. Yemen: First Batch of Emirati Abu al-'Abbas Brigade Fighters in Ta'izz Reaches Aden. al-Quds al-'Arabi. 28 August.

  • al-Husni, A. 2017. Salafi Shaikhs in Aden: Zayid or Death. al-Akhbar. 31 October.

  • al-Jazeera. 2015. Yemeni Forces Seize Provincial Capital from Houthis. 18 December.

  • al-Jazeera. 2017. Aden: Troops Killed in Attack on Government Security HQ. 5 November.

  • al-Jazeera. 2018. The al-Mahrah Oil Pipeline: Saudi Greed and Local Resistance. 9 October.

  • al-Khalij. 2018. Baum: Transitional Council is UAE's Voice. 9 October.

  • Al-Maqtari, B. 2017. The evolution of militant salafism in Taiz. San’a: Sanaa Center for Strategic Studies.

    Google Scholar 

  • al-Mashhad al-Yamani. 2018. Tariq Salih's Forces Engage in Confrontation, Opening of New Fronts against the Huthis. 8 April.

  • al-mayadin.net. 2018. South Yemen Is Under a Regressive Saudi-Emirati Occupation. 10 October.

  • Al-Mujahed, A. and K. Fahim. 2017. Yemen's Rebel Alliance Appears to Fracture as Clashes Leave Dozens Dead. Washington Post. 2 December.

  • Al-Mujahed, A. and S. Raghavan. 2018. Yemen's War Is So Out of Control, Allies Are Turning on One Another. Washington Post. 3 February.

  • al-Muslimi, F. 2015a. Saudi Airstrikes against Yemen a First. al-monitor.com. 2 April.

  • al-Muslimi, F. 2015b. The Southern Question: Yemen's War Inside the War. Diwan. 8 July.

  • al-Naqib, 'A. 2017. What Are the Expected Scenarios Now that Tension Has Returned to Aden? Rai al-Yawm. 17 October.

  • al-Sakkar, N. 2015. Yemen's Taiz Sinks into the Abyss as Salafis Fight War of Revenge. middleeasteye.net. 2 December.

  • al-Sharq. 2017. The Southern Movement: The UAE Has Occupied Yemen. 5 September.

  • Alwly, A. 2016. Assassinations, Chaos Cripple Yemen's Aden. al-monitor.com. 18 January.

  • Alyahya, M. 2015. Why Did Saudi Arabia Intervene in Yemen? al-monitor.com. 3 June.

  • Ardemagni, E. 2016. UAE's Military Priorities in Yemen. ISPI Commentary. Rome. 28 July.

  • Ardemagni, E. 2018. The UAE's Security-Economic Nexus in Yemen. Sada. 19 July.

  • Arrabyee, N. 2016a. Rising Extremism in Yemen. Sada. 19 February.

  • Arrabyee, N. 2016b. Saudi Arabia's Unholy War. Sada. 3 March.

  • Associated Press. 2018. Fear Grips Yemen's Aden as Deadly Attacks Target Clerics. 5 April.

  • Balch-Lindsay, D., and A. Enterline. 2000. Killing time: the world politics of civil war duration. International Studies Quarterly 44 (4): 615–642.

    Article  Google Scholar 

  • Balch-Lindsay, D., A. Enterline, and K. Joyce. 2008. Third-party intervention and the civil war process. Journal of Peace Research 45 (3): 345–363.

    Article  Google Scholar 

  • Bayoumy, Y., N. Browning and M. Ghobari. 2016. How Saudi Arabia's War in Yemen Has Made al-Qaeda Stronger—and Richer. Reuters. 8 April.

  • Boussaid, F. 2021. Brothers in arms: Morocco’s military intervention in support of Mobutu of Zaire during the 1977 and 1978 Shaba crisis. International History Review 43 (1): 185–202.

    Article  Google Scholar 

  • Brandt, P., D. Mason, M. Gurses, N. Petrovski, and D. Radin. 2008. When and how the fighting stops. Defence and Peace Economics 19 (6): 415–434.

    Article  Google Scholar 

  • Browne, G. 2018. Who Are the Yemeni Ground Forces Fighting in Hodeidah? The National. 14 June.

  • Carapico, S. 2000. Yemen and the Aden-Abyan Islamic Army. MERIP Reports. October.

  • Coletta, D. 2013. Principal-agent theory in complex operations. Small Wars and Insurgencies 24 (2): 306–321.

    Article  Google Scholar 

  • Collier, P., A. Hoeffler, and M. Soederbom. 2004. On the duration of civil war. Journal of Peace Research 41 (3): 253–273.

    Article  Google Scholar 

  • Cunningham, D. 2006. Veto players and civil war duration. American Journal of Political Science 50 (4): 875–892.

    Article  Google Scholar 

  • Cunningham, D. 2010. Blocking resolution: how external states can prolong civil wars. Journal of Peace Research 47 (2): 115–127.

    Article  Google Scholar 

  • Dahlgren, S. 2010. The snake with a thousand heads: the southern cause in Yemen. Middle East Report 256: 28–33.

    Google Scholar 

  • Dahlgren, S. 2018. The Southern Transitional Council and the War in Yemen. Middle East Research and Information Project. 26 April.

  • Desrosiers, M., and S. Vucetic. 2018. Causal claims and the study of ethnic conflict. Journal of Global Security Studies 3 (4): 483–497.

    Article  Google Scholar 

  • Diwan, K., and F. Alasrar. 2016. Gulf states struggle to achieve goals in Yemen’s war. Washington, DC: Arab Gulf States Institute in Washington.

    Google Scholar 

  • Dixon, J. 2009. Emerging consensus: results from the second wave of statistical studies on civil war. Civil Wars 11 (2): 121–136.

    Article  Google Scholar 

  • Edelstein, D. 2008. Occupational hazards. Ithaca, NY: Cornell University Press.

    Google Scholar 

  • El Yaakoubi, A. 2017. UAE builds up Yemen regional army but country fragments. Reuters. 3 May.

  • Elbadawi, I. and N. Sambanis. 2000. External Intervention and the Duration of Civil Wars. Washington, DC: World Bank.

  • Eleftheriadou, M. 2021. Non-State Armed Actors and Contested Sovereignties in Internationalized Civil Wars: The Case of Yemen's Civil War (2015-). International Politics (forthcoming).

  • Eleiba, A. 2018. Al-Qaeda in Yemen. al-Ahram Weekly. 4–10 October.

  • Fenton-Harvey, J. 2018. Al-Qaeda's Future in a War-Torn Yemen. Sada. 25 September.

  • Forster, R. 2017. The southern transitional council: implications for Yemen’s peace process. Middle East Policy 24 (3): 133–144.

    Article  Google Scholar 

  • Ghobari, M. and Y. Bayoumy. 2016. Wave of Aden Killings Tests Gulf Role in Yemen. Reuters. 9 February.

  • Gleditsch, K., and K. Beardsley. 2004. Nosy neighbors: third-party actors in Central American conflicts. Journal of Conflict Resolution. 48 (3): 379–402.

    Article  Google Scholar 

  • Hedges, M., and G. Cafiero. 2017. The GCC and the muslim brotherhood. Middle East Policy 24 (1): 129–153.

    Google Scholar 

  • Hironaka, A. 2005. Neverending wars. Cambridge, Mass.: Harvard University Press.

    Book  Google Scholar 

  • Hokayem, E. and D. Roberts. 2017. The war in Yemen. Survival 58 (6): 157–186.

  • Hubbard, B. and N. Youssef. 2017. Yemen's War Enters a Dark Stage as Rebels Squeeze the Capital. New York Times. 23 December.

  • Ibish, H. 2017. The UAE's Evolving National Security Strategy. Issue Paper No 4. Washington, DC: Arab Gulf States Institute in Washington.

  • International Crisis Group. 2016. Yemen: Is Peace Possible? Middle East Report No. 167. 9 February.

  • Jenne, E. and M. Popovic. 2017. Managing Internationalized Civil Wars. Oxford Research Encyclopedia of Politics. Oxford: Oxford University Press.

  • Johnsen, G. 2013. The last refuge: Yemen, al-Qaeda and America’s war in Yemen. New York: W. W. Norton.

    Google Scholar 

  • Juneau, T. 2016. Iran’s policy towards the Houthis in Yemen. International Affairs 92 (3): 647–663.

    Article  Google Scholar 

  • Kendall, E. 2018. Contemporary Jihadi Militancy in Yemen. Policy Paper 2018–7. Washington, DC: Middle East Institute.

  • Khan, T. 2017. Al Qaeda Exploits Schisms and Shortages to Thrive in Yemen. The National. 20 July.

  • Knights, M. and A. Mello. 2015. The Saudi-AUE War Effort in Yemen (Part 1). Policy Watch No. 2464. Washington, DC: Washington Institute for Near East Policy.

  • Lacina, B. 2006. Explaining the severity of civil wars. Journal of Conflict Resolution 50 (2): 276–289.

    Article  Google Scholar 

  • Lawson, F. 2019. Foreign military intervention and the duration of civil wars revisited. Jadavpur Journal of International Relations 23 (1): 232–241.

    Article  Google Scholar 

  • Legrenzi, M., and F. Lawson. 2016. Saudi Arabia calls out Hezbollah: Why now? Middle East Policy 23 (2): 31–43.

    Article  Google Scholar 

  • Linebarger, C. and A. Enterline. 2016. Third party intervention and the duration and outcomes of civil wars. In What Do We Know about Civil Wars?, ed. T. Mason and S. Mitchell. Lanham, MD: Rowman and Littlefield.

  • Lockyer, A. 2011. Foreign Intervention and Warfare in Civil Wars. Review of International Studies 37 (5): 2337–2364.

    Article  Google Scholar 

  • Lounsbery, M. 2016. Foreign military intervention, power dynamics and rebel group cohesion. Journal of Global Security Studies 1 (2): 127–141.

    Article  Google Scholar 

  • Lyall, J., and I. Wilson. 2009. Rage against the machines: explaining outcomes in counterinsurgency wars. International Organization 63 (1): 67–106.

    Article  Google Scholar 

  • Mahmood, A. 2017a. Yemen rebels lose more territory in Hodeidah. The National. 10 December.

  • Mahmood, A. 2017b. Yemen forces close in on Sanaa after breaking through Rebel-Held Hills. The National. 18 December.

  • Mahmood, A. 2018a. Houthis suffer major losses in Yemen's Hodeidah. The National. 20 February.

  • Mahmood, A. 2018b. Elite Yemeni forces hit AQAP fighters near Shabwa. The National. 21 July.

  • Mahmood, A. 2018c. Civilian killed in bomb targeting South Yemen Commander. The National. 24 July.

  • Mahmood, A. 2018d. Yemenis in Hadramawt Demand UAE-Backed Forces Take Over Security. The National. 26 July.

  • Mahmood, A. 2018e. Rival Huthi Factions battle for leadership in Yemen. The National. 1 October.

  • Mahmood, A. and N. Al Wasmi. 2018. Yemeni forces make key gain in campaign to retake Rebel-Held Port. The National. 8 February.

  • Mason, T., J. Weingarten, and P. Fett. 1999. Win, lose or draw: predicting the outcome of civil wars. Political Research Quarterly 52 (2): 239–268.

    Article  Google Scholar 

  • Michael, M., T. Wilson and L. Keath. 2016. Yemen: US allies strike deals with al-Qaida in war on rebels. Associated Press. 6 August.

  • Michaeli, M. 2018. UAE deploys troops to Yemeni Island, imperiling alliance. Associated Press. 5 May.

  • middleeasteye.net. 2015. Al-Qaeda Seizes Key Southern Town in Yemen. 2 December.

  • middleeasteye.net. 2017a. Yemen War: Demands for Southern Independence Split Coalition. 18 March.

  • middleeasteye.net. 2017b. Brothers No More: Yemen's Islah Party Faces Collapse of Aden Alliances. 21 October.

  • middleeasteye.net. 2017c. Yemen's Salafi Warlord—Armed by Riyadh, Branded a Terrorist by Riyadh. 27 October.

  • middleeasteye.net. 2018a. How the UAE Put Aden Under the Control of the Militias. 1 February.

  • middleeasteye.net. 2018b. Aden Hitmen Pick Off Yemen President's Supporters, One By One. 16 February.

  • middleeasteye.net. 2018c. Tensions Rise on Yemen's Socotra after UAE Deployment. 5 May.

  • middleeasteye.net. 2018d. UAE Forced Hadi to Support Hodeidah Assault Against His Will. 13 June.

  • middleeasteye.net. 2018e. Tensions Heighten between Pro-Hadi Groups in Yemen's Taiz. 30 August.

  • middleeasteye.net. 2018f. Saudi Military Colonialism Sparks Protest Movement in Yemen's East. 30 September.

  • middleeasteye.net. 2018g. Former Yemen Allies Furious as UAE Assassination Campaign Exposed. 17 October.

  • middleeastmonitor.com. 2017. Pro-UAE Militias Escalate Attack on al-Islah in Yemen. 25 October.

  • Mitton, J. 2017. Rivalry intervention in civil conflicts. Canadian Foreign Policy Journal 23 (3): 277–291.

    Article  Google Scholar 

  • Mohamed, A. and M. Al Qalisi. 2017. The end of the unholy alliance as Yemen's Saleh dumps the Houthis. The National. 2 December.

  • Mukhashaf, M. 2017. Thousands protest at Yemen President's sacking of Southern Leaders. Reuters. 4 May.

  • Nagi, A. 2018. Yemen's other proxy struggle. Diwan. 19 October.

  • Nasser, A. 2016. How Long Can Saudi Arabia Afford Yemen War. al-monitor.com. 21 January.

  • Naylor, H. 2015. Yemen is turning into Saudi Arabia's Vietnam. Washington Post. 13 November.

  • Partrick, N. 2015. Saudi Arabia's Yemen Gambit. Sada. 1 October.

  • Partrick, N. 2016. Saudi Arabia's Problematic Allies against the Houthis. Sada. 12 February.

  • Partrick, N. 2017a. The UAE's War Aims in Yemen. Sada. 24 October.

  • Partrick, N. 2017b. The Saudi and Emirati Conundrum After Saleh. Sada. 18 December.

  • Pearson, F. 1974. Foreign military intervention and domestic disputes. International Studies Quarterly 15 (3): 259–290.

    Article  Google Scholar 

  • Popp, R. 2015. War in Yemen: Revolution and Saudi Intervention. CSS Analyses in Security Policy No. 175. Center for Security Studies. ETH Zurich. June.

  • Rafi, S. 2015. Saudis desperate as they are not winning the war in Yemen. Asia Times. 16 October.

  • Raghavan, S. 2018. Who is Killing Yemen's Clerics? Washington Post. 28 August.

  • Rai al-Yawm. 2017. Will KSA Conduct Radical Revision of its Alliances in Yemen? 4 April.

  • Regan, P. 2000. Civil wars and foreign powers. Ann Arbor: University of Michigan Press.

    Book  Google Scholar 

  • Regan, P. 2010. Intervention into civil wars: A retrospective survey with prospective ideas. Civil Wars 12 (4): 456–476.

    Article  Google Scholar 

  • Reuters. 2018. Yemen's southern separatists attack military academy in Aden. 18 August.

  • Salehyan, I. 2010. The delegation of war to rebel organizations. Journal of Conflict Resolution 54 (3): 493–515.

    Article  Google Scholar 

  • Salehyan, I., D. Siroky, and R. Wood. 2014. External rebel sponsorship and civilian abuse. International Organization 68 (3): 633–661.

    Article  Google Scholar 

  • Salisbury, P. 2015. Yemen and the Saudi-Iranian ‘Cold War’. London: Royal Institute of International Affairs.

    Google Scholar 

  • Salisbury, P. 2017. Yemen: National Chaos, local order. London: Royal Institute of International Affairs.

    Google Scholar 

  • Salisbury, P. 2018. Yemen: After Hodeidah. Washington, DC: Arab Gulf States Institute in Washington.

    Google Scholar 

  • Salisbury, P. 2016. The UAE's Yemen Pivot Could Make Differences with Riyadh Unbridgeable. World Politics Review. 28 June.

  • Samir, M. 2017. After It Flourished at the UAE's Hands, MB Continues to Lie about Abu Dhabi's Role in Socotra. al-Fajr. 6 April.

  • Schmitz, C. 2014. The fall of Amran and the future of the Islah Party. Washington, DC: Middle East Institute.

    Google Scholar 

  • Schmitz, C. 2018. Hadi’s political chaos may Hamper Yemen talks. Washington, DC: Middle East Institute.

    Google Scholar 

  • Schmitz, C. 2016. Yemen on a Road to Nowhere. Washington, DC: Middle East Institute.

  • Snyder, G. 1984. The security dilemma in alliance politics. World Politics 36 (4): 461–495.

    Article  Google Scholar 

  • Stein, A. and M. Cantin. 2021. Crowding Out the Field. International Interactions (forthcoming).

  • Sullivan, P., and J. Karreth. 2015. The conditional impact of miltiary intervention on internal armed conflict outcomes. Conflict Management and Peace Science 32 (3): 269–288.

    Article  Google Scholar 

  • Terrill, A. 2014. Iranian involvement in Yemen. Orbis 58 (3): 429–440.

    Article  Google Scholar 

  • The National. 2018. UAE Supported Coalition Makes Advances across Yemen. 15 February.

  • Walter, B. 2009. Bargaining failures and civil war. Annual Review of Political Science 12: 243–261.

    Article  Google Scholar 

  • Zweiri, M. 2016. Iran and political dynamism in the Arab world: The case of Yemen. Digest of Middle East Studies 25 (1): 4–18.

    Article  Google Scholar 

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  1. International Relations at the Emirates Diplomatic Academy, Abu Dhabi, United Arab Emirates

    Fred H. Lawson

  2. Government Emeritus of Mills College, Oakland, USA

    Fred H. Lawson

  3. Box 249, Bodega Bay, CA, 94923, USA

    Fred H. Lawson

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Lawson, F.H. Why foreign military interventions prolong civil wars: lessons from Yemen. Int Polit 59, 1167–1186 (2022). https://doi.org/10.1057/s41311-021-00357-6

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