Synthesising the Mechanisms of Peacekeeping Success

This study investigates the mechanisms linking institutional and local factors to the success of United Nations peacekeeping operations. Success is defined as reducing battle-related deaths and protecting civilians. While variations in factors across peacekeeping operations are assumed to explain differing success rates, the specific reasons why certain factors contribute, or limit success remain unclear. The study examines institutional factors, such as the United Nations Security Council’s (UNSC) interest, reflected in the size and composition of deployments. Local factors, particularly support from local actors, are also examined. A comparative analysis of the United Nations Mission in Sierra Leone (UNAMSIL) and the United Nations Organization Stabilization Mission in the Democratic Republic of the Congo (MONUSCO) was conducted due to their similar contexts yet differing outcomes. A qualitative analysis of resolutions and Secretary-General reports revealed that UNAMSIL’s larger deployment and higher local support facilitated better violence mitigation and protection of civilians. These factors allow peacekeepers to increase the cost of violence, overcome combatants’ commitment problems, protect civilians and gain legitimacy. In contrast, MONUSCO’s smaller deployment and lack of local support limited its success. These findings address a gap in literature, offering valuable insights into the mechanisms of peacekeeping success. Moreover, the findings contribute to our understanding of why UNAMSIL succeeded while MONUSCO failed, thus providing practical implications. In particular, the securing of host-state support is critical to peacekeeping success. The findings further indicate that institutional and local factors are jointly sufficient for a successful United Nations peacekeeping operation, which provides direction for future research.