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External Support and Civil War Termination

External Support and Civil War Termination

Photo credit: Nick Ares

This analysis summarizes and reflects on the following research: Sawyer, K., Cunningham, K. G., & Reed, W. (2017). The role of external support in civil war termination. Journal of Conflict Resolution61(6), 1174-1202.

Talking Points

  • When rebel groups receive outside financial support, civil wars are more than two times less likely to end compared to when rebels receive non-financial support.
  • When states receive foreign military support (troops), civil wars last longer. When rebels receive foreign military support (troops) civil wars are shorter.


Civil wars have emerged as one of the more common forms of armed conflict in the last few decades. Factors such as the number of warring parties, foreign military intervention, and the blurred line between civilians and combatants make civil wars especially difficult to resolve. Furthermore, although civil wars occur within a single country, the international community rarely views them merely as domestic problems. External governments and international organizations become involved (either on humanitarian grounds or in self-interest), adding otherwise nonexistent levels of financial or military support that most often makes resolving the conflict much more difficult. This study looks specifically at how external “fungible” support (mainly direct financial support) provided to rebels may influence the prospects for civil war termination. Indeed, this research shows that foreign involvement only makes matters worse and that, by providing financial support to rebels, external governments can prolong the war much more than previously realized.

The author’s hypothesis suggests that perhaps fungible support can decrease the chance of resolution by creating uncertainty about the rebel group’s ability to maintain the resources needed to wage war against their government, which in turn limits options for resolution. By not knowing how much of the outside fungible support will translate into rebel firepower, governments are less likely to negotiate for peace because they cannot accurately measure the rebel’s ability to maintain fighting.

The authors used multiple forms of statistical analysis to identify the relationship between levels of fungible support and civil war resolution and to contrast the effects of fungible support with direct military support, such as guns, troops, and equipment.  In all three methodological approaches, the authors found fungible support from external parties was consistently shown to be associated with longer wars, but that providing troops may be linked to shorter wars. The authors argue that this relationship may exist because it is unclear to governments to what extent fungible support actually increases rebels’ military capability -leading governments to overestimate their own ability to win wars. As an example, when outside actors provide weapons to rebels, it is easy to draw the conclusion that more guns make a more deadly/efficient opponent. However, when fungible assistance is given, rebel groups could hypothetically use that money to either a) buy more guns or b) pay out bribes. Because of the ambiguity of how rebels use fungible support, governments are less equipped to assess the likelihood of their victory over the rebels, and thus less likely to come to a peace agreement and more likely to continue fighting.

Another important finding of this study sheds light on what we know about the major civil war parties and their respective roles in ending the conflict. When reviewing past research on this topic, the authors found that the state is commonly blamed as the party most opposed to a peace agreement. However, if foreign financial support is impactful enough to cause the cost of rebel fighting to go down (and their capacity to fight to go up), the traditional power imbalance between state and rebel groups shifts to favor the rebels and continued fighting becomes more desirable for the rebels. In this scenario, it is the rebels’ inability to stop fighting and negotiate for peace that leads to ongoing conflict. Therefore, the results of this study show that fungible support may give both the state and the rebel forces a level of (perhaps misguided) confidence in their own military capabilities, providing them both with an incentive to keep fighting.

Contemporary Relevance

Over the last 50 years, many outside governments have chosen to support one side of a civil war. Not only can such support prolong wars, as this study has shown, but it can also be used in unintended ways or used against the outside governments in the years that follow. The ongoing Syrian war provides the most timely example, where many states have debated whether or how to support the Syrian opposition. Syria is especially relevant to this research because the war-extending effects of fungible support are compounded by the vast amounts of financial support flowing to both the Syrian government and the various rebel groups. In the case of the United States, this debate is especially heated considering how arms supplied by the U.S. to support factions in Afghanistan and Iraq have traded hands over the years—and now have become a major portion of the fighting power of the Taliban, ISIS, and other groups in open conflict against the U.S. and/or its allies. This research adds to our understanding of the dangers of supporting rebel forces during civil wars by showing that even non-military aid, such as financial support, can be detrimental to the peace process and actually prolong the fighting by substantial durations.

Practical Implications

This research provides insight into the consequences of foreign party involvement in civil wars. While war participation of any form should be discouraged, lessons from this study show that some forms of participation are worse than others, potentially causing civil wars to last longer than they would have had outside parties not been involved. Outside parties should reconsider their policy for civil war intervention and weigh the benefits of providing military or financial support with the high costs of continued war and the uncertainty of post-civil war reconstruction, where weapons and financial support often trade hands to groups that will become even greater threats in the future. These are important talking points for advocates who want to inform policy-makers, the media, and the public when military interventions are being discussed as options. Finally, the human costs of war must not be taken out of any abstraction. A potential shortening of a civil war when rebels receive foreign military support must be weighed against the expected casualties. That brings us back to an underlying notion of always advocating for and using the numerous viable nonviolent alternatives that exist.

Continued Reading

In Syria, Militias Armed by the Pentagon Fight Those Armed by the CIA By Nabih Bulos, W.J. Hennigan, and Brian Bennett. LA Times, 2016.

Syria’s Paradox: Why the War Only Ever Seems to Get Worse By Max Fisher. New York Times, 2016.

Private Donors’ Funds Add Wild Card to War in Syria By Ben Hubbard. New York Times, 2013.

Keywords: civil wars, conflict outcomes, external support, game theory

The above analysis is from Volume 2, Issue 4, of the Peace Science Digest.


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