Hegemonic Competition, Alliance Networks, and Strategic Autonomy: Strategy in an Emerging Multipolar Geopolitical Order

The international system is moving away from the relatively coherent post-Cold War order toward layered and contested multipolarity. Military power is diffusing; economic interdependence is increasingly securitized; alliance commitments are exposed to domestic bargaining; and states are embedded in overlapping security, technology, financial, and industrial networks. This paper develops a general framework for alliance choice and strategic autonomy under these conditions. A stylized model with linear preferences and linear technologies treats the United States and China as competing network centers: the sponsor chooses whether and how strongly to support its network, while smaller states compare alternative networks according to security, geography, productivity and supply-chain effects, transfers, political-assimilation costs, and indigenous capability. The model distinguishes decentralized allied defense from a network-planner benchmark and derives an alliance transfer multiplier theorem for alliance transfers. Under a frictionless one-for-one reallocation from direct U.S. military spending to an ally transfer, if the induced present-value increase in allied military effort exceeds one per unit transferred, the alliance multiplier raises U.S.-alliance military capability and, through the modeled hegemonic-power channel, U.S. welfare; allied welfare also rises under the maintained assumptions when the multiplier exceeds one. Although the local theorem holds membership fixed, entry can amplify the effect through network size, productivity, and further induced military effort. Conversely, transfer cuts near participation thresholds can trigger nonlinear alliance weakening. The formal logic is linked to a four-index comparative diagnostic applied across fourteen states. Strategic autonomy is defined not as equidistant neutrality but as the capacity to preserve meaningful choice under pressure. South Korea is retained as a brief hard-case illustration in Appendix A.