兰德-平衡法案 - 盟友如何回应有限的美国裁员（英）

During President Donald Trump’s second term, his administration indicated a desire to retrench militarily from Europe and possibly elsewhere to promote greater allied burden-sharing. Assessing whether this change would advance U.S. interests involves con-sidering several possible effects: the behavior of U.S. rivals, regional stability, U.S. defense budgets, and the behavior of U.S. allies. In this analysis, RAND researchers focus on the last of these effects: the behavior of U.S. allies. The researchers exam-ine the responses of West Germany, South Korea, Japan, and Taiwan in the 1960s and 1970s to a shift in U.S. strategy that involved limited U.S. force reductions and other forms of retrenchment. The United States also sought to stabilize relations with its rivals, the Soviet Union and the People’s Repub-lic of China (PRC), in this period. If the Trump administration undertakes a similar strategic shift, these cases can provide a starting point for predict-ing the likely effects. However, the effects of more-dramatic changes in U.S. strategy would require additional analysis.The Policy Debate: Two Schools of ThoughtDisagreements about how allies would respond to U.S. retrenchment figure prominently in the debate about U.S. global strategy. There are two perspec-tives in this debate. Deep engagement embraces core elements of U.S. strategy since the end of World War II, including a vast network of alliances and security partnerships, a large forward military presence, and a willingness to use force to defend allies and international norms. Deep engagement assumes that this high level of U.S. military pres-ence in East Asia, Europe, and the Middle East promotes stability, U.S. security, and prosperity. Restraint calls for reduced U.S. military engage-ment in one or more of these key regions. Deep engagers and restrainers disagree on how allies will react to retrenchment and the implica-tions for U.S. interests and conflict risk. Deep engagers fear that allies might align with powerful neighbors or lack the resources to balance threats effectively. They also worry that allies might pursue nuclear weapons or engage in destabilizing policies. Conversely, restrainers believe that retrenchment will curb free riding and prompt allies to adopt more-prudent stances toward rivals. They view deep engagers’ fears of bandwagoning (i.e., aligning with a powerful aggressor) as exaggerated, while deep engagers see restrainers as overly optimistic about allies’ abilities to counter threats without U.S. leadership.RESEARCH BRIEFBalancing Act—How Allies Have Responded to Limited U.S. Retrenchment 2To assess how each ally responded to past U.S. retrenchment, the researchers addressed the following questions:•What steps did the ally take to try to limit U.S.retrenchment?•Did the ally shift its alignment away from theUnited States and toward the shared rival?•Did the ally increase defense burden-sharing ordeepen ties with other partners?•Did the ally adopt a less con