The article develops a game theoretical model for the evolution of various regionalism projects. It contends that regionalism in the post-World War II (WWII) world has almost always evolved in the shadow of extraregional great powers (EGPs), with the United States being the principal, but not the only, EGP. As such, how regional great powers (RGPs) and small-to-medium states (SMSs) within a region interact with each other in the shadow of EGPs are critical to the evolution of different regionalism projects. This setup leads to a game theoretical framework. Among the various regionalism projects, regionalism in Central Asia is an intriguing case. The model developed in this article implies that the sometimes competitive and sometimes cooperative interaction among SMSs, EGPs, and RGPs can best explain the historical dynamics of the regionalism project in Central Asia. In particular, the model explains why the Shanghai Cooperation Organization, the regionalism project that has been proclaimed to be dead or close to be dead by many pundits, has become the more resilient and visible among the many regionalism projects within the region. The model also applies to other regionalism projects.

中文翻译：

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区域外大国阴影下的区域主义：中亚及其他地区的博弈论解释†

本文为各种区域主义项目的演变发展了一个博弈理论模型。它认为，二战后 (WWII) 世界的地区主义几乎总是在地区外大国 (EGP) 的阴影下发展，美国是主要但不是唯一的 EGP。因此，一个地区内的地区大国 (RGP) 和中小国家 (SMS) 如何在 EGP 的阴影下相互作用，对于不同地区主义项目的演变至关重要。这种设置导致了博弈论框架。在各种地区主义项目中，中亚地区主义是一个耐人寻味的案例。本文中开发的模型意味着 SMS、EGP、RGPs 最能解释中亚地区主义项目的历史动态。特别是，该模型解释了为什么上海合作组织这个被许多专家宣布已死或接近死的区域主义项目，在该地区的众多区域主义项目中变得更具弹性和可见性。该模型也适用于其他区域主义项目。