Under what conditions can UN military peacekeeping operations (PKOs) succeed in contexts of civil war? This is an important question given the prevalence and cost of civil wars and the high, yet not always fulfilled, expectations of very costly military PKOs as responses to them by the international community. Yet, the academic and policy debates on this question are as long-standing as they are unresolved. Our article contributes to existing scholarship in several ways. First, adopting a nuanced and multi-dimensional definition of success that considers violence, displacement, and contagion as its 3 essential components, we identified 19 cases of full or partial successes, and 13 full or partial failures, covering all 32 UN military PKOs deployed to civil war settings. Second, we develop an original dataset and analytical framework that identifies a wide range of plausible factors related to the dynamics of both the intervention and the underlying conflict it is meant to address. Third, applying qualitative comparative analysis to our dataset of these 32 military PKOs, our key finding is that what matters most and consistently across all of these missions is the presence or absence of domestic consent to, and cooperation with, deployed PKOs.

在内战背景下，联合国军事维和行动（PKO）在什么条件下才能取得成功？考虑到内战的普遍性和代价，以及国际社会对代价高昂的军事维和行动的高期望但并不总是得到满足，这是一个重要问题。然而，关于这个问题的学术和政策争论由来已久，一直没有得到解决。我们的文章以多种方式为现有的学术做出了贡献。首先，采用细致入微的多维成功定义，将暴力、流离失所和传染作为其 3 个基本组成部分，我们确定了 19 个完全或部分成功的案例，以及 13 个完全或部分失败的案例，涵盖了部署的所有 32 个联合国军事维和行动到内战环境。第二，我们开发了一个原始数据集和分析框架，该框架确定了与干预及其旨在解决的潜在冲突的动态相关的各种合理因素。第三，将定性比较分析应用于我们对这 32 个军事维和行动的数据集，我们的主要发现是，在所有这些任务中最重要且始终如一的是国内是否同意已部署的维和行动并与之合作。