Why do some international agreements yield more cooperation than others? I argue that the network context of agreements conditions their effectiveness. I focus on bilateral defense cooperation agreements (DCAs), which promote defense activities like joint military exercises, peacekeeping, arms trade, and the sharing of classified information. Because DCAs emphasize ongoing cooperative actions, they offer an ideal setting to assess treaty effectiveness. The analysis shows that when agreements are embedded in transitive “friend of friend” relations, characterized by extensive ties to common third parties, they generate higher levels of cooperation. I argue that this network effect is the result of policy convergence. When states share ties with common third parties, their own policies become more closely aligned, and this alignment in turn reduces the costs and increases the benefits of cooperative actions. The theory and findings developed here apply to a wide array of cooperative interactions across multiple issue areas. The effectiveness of international agreements depends on network context.

中文翻译：

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网络环境和国际协议的有效性


为什么一些国际协议比其他协议产生更多的合作？我认为协议的网络环境决定了其有效性。我重点关注双边防务合作协议（DCA），该协议促进联合军事演习、维和、武器贸易和机密信息共享等国防活动。由于 DCA 强调持续的合作行动，因此它们提供了评估条约有效性的理想环境。分析表明，当协议嵌入到以与共同第三方的广泛联系为特征的传递性“朋友的朋友”关系中时，它们会产生更高水平的合作。我认为这种网络效应是政策趋同的结果。当国家与共同的第三方建立联系时，它们自己的政策就会变得更加紧密一致，而这种一致性反过来又会降低合作行动的成本并增加合作行动的收益。这里提出的理论和研究结果适用于跨多个问题领域的广泛合作互动。国际协议的有效性取决于网络环境。