Ensuring military access to the territory of allies and partners in the Indo-Pacific in the event of a future conflict with China is a critical concern for U.S. policymakers. The physical and political geography of the region sharply limits U.S. options to such an extent that some allied and partner decisions to provide or refuse access could determine the outcome of a conflict. A clearer understanding of how and why U.S.

allies and partners are likely to make conflict-phase access decisions, and what U.S. policymakers can do to affect the decisions ahead of time, is therefore essential. In this report, the authors examine how U.S. allies and partners make conflict-phase access decisions and how the United States and the U.S. Air Force (USAF) might be able to influence decisions in advance.

The authors developed a framework for assessing such decisionmaking, then applied it to five specific allies and partners in the region (Japan, the Philippines, Singapore, Indonesia, and India) to assess their strategic outlooks, internal politics, and economic incentives and to identify the peacetime policy levers that are most promising for affecting the states decisionmaking.