The Diplomatic Core: The Determinants of High-Level U.S. Diplomatic Visits, 1946–2010

Face-to-face diplomacy is an important feature of international relations. But when and why do high-level diplomatic interactions occur? We examine different theoretical perspectives using a new dataset of diplomatic visits by the US President and Secretary of State. We argue for assessing these visits along two dimensions. First, we posit that the degree of discretion or constraint in the diplomatic calendar falls along a spectrum. Strategic and domestic factors are at opposite extremes while diplomatic routines fall in the middle. Second, we consider the convergence in the relative influence of these sets of factors across the President’s and the Secretary’s calendars. We develop and test hypotheses about the determinants of visits by the President and Secretary of State across twelve presidencies from 1946 to 2010. Overall, the travels of the President and Secretary converge to serve a set of priorities that derive from a fairly stable set of national interests and from diplomatic routine. We observe that the President effectively retraces the footsteps of the Secretary more than the reverse. We find some evidence of domestic (including individual-level) influences on diplomacy, but only limited evidence that times of crisis produce distinct patterns in face-to-face encounters.面对面外交是国际关系的重要特征。但高层外交互动究竟在何时、因何发生？本研究依托美国总统（US President）与美国国务卿（Secretary of State）外交出访的全新数据集，对不同理论视角展开检验。我们主张从两个维度对上述外交出访进行评估：其一，我们提出，外交日程中的自由裁量与约束程度呈现连续谱系：战略因素与国内因素分处谱系两端，而外交日常事务则居于中间地带。其二，我们考量总统与国务卿外交日程中，上述两类因素相对影响力的趋同情况。我们针对1946年至2010年间共12届总统任期内，美国总统与美国国务卿外交出访的决定因素构建并检验了相关假说。总体而言，总统与国务卿的出访行程趋于一致，以服务于源自相对稳定的国家利益与外交日常事务的一系列优先事项。我们发现，总统往往会追随国务卿的出访足迹，而非反之。我们找到了部分证据表明国内因素（包括个体层面因素）会对外交活动产生影响，但仅有有限证据证明危机时期会在面对面外交接触中形成独特模式。