There is a growing sense that U.S. military effectiveness has been on the wane in recent years. Is this the case? If so, what are the reasons for the decay in American combat performance? We first examine the available systematic evidence for American military decline, showing that the United States has indeed experienced a drop in the quality of outcomes of its military contests. Observers have offered a number of explanations for declining American military success, most predominantly an increase in intrastate conflict after the Second World War. After showing that a decline in performance is observed even after fully excluding intrastate conflict, we propose an alternative explanation: the increasing distance-from-home at which the United States has been fighting. Distance is tyrannical: it saps military strength and increases the cost of contests, even as it reduces U.S. expertise and motivations to prevail. We then show that the distance from home at which the United States fights is the best predictor of the outcome of the conflict. We conclude by noting some avenues for future research and policy implications as the world returns to great power competition.
Congressional-Executive Relations and the Use of Military Force
Despite the widespread belief in an Imperial Presidency and the purported cession of the war-making power to the executive after Truman’s unapproved Korean War of 1950-53, no President has actually entered into a major war without formal congressional approval in the last seven decades. Instead, Presidents since Eisenhower have consistently asked Congress for authorization before risking large-scale conflict. While it is certainly true that many uses of force in the postwar era have lacked congressional approval or seen Presidents attempt to substitute some form of international approval for that of Congress, these conflicts have been distinctly smaller in scale than those undertaken with Congress’s formal backing. There is little evidence of an Imperial Presidency when it comes to a supposed increasing scale of military operations undertaken without congressional approval over time. Furthermore, international force authorizations are not viable substitutes for congressional approval. While international authorizations can boost public support for an intervention in the short-term, only express authorization from Congress provides the long-term commitment a president needs to commit to a major conflict.
Power, Parity and Proximity (with Erik Gartzke, Alex Braithwaite, and Lauren Gilbert)
Research debating competing perspectives on power and war has yet to address the endogenous impact of proximity. If power declines in distance, then power relations between two nations differ at different points on the globe. Claims about the impact of parity or preponderance on conflict and peace then really only apply to particular points or regions in the space separating borders or national capitals. We use a formal bargaining model to demonstrate that dyads should be most prone to fight in places where each state’s capabilities, discounted by distance, are roughly at parity. We then assess this relationship empirically, introducing the directed dyad year location unit-of-analysis to capture the impact of geographic distance on power and the propensity to fight. Results confirm that disputes are most likely at locations where the distance-weighted capabilities of nations are roughly equal.
The Taiwan Question in U.S. Grand Strategy (with James Lee)
A debate over the United States’ relationship with Taiwan has recently been the focus of scholarly attention. Notably, the discussion has seen major disagreement amongst policy-makers, academics, and other analysts otherwise inclined to agree with one another on U.S. alliance commitments. We suggest that this lack of agreement stems from the absence of clear prescriptive recommendations given by many of the most prominent grand strategies promoted in the United States today. This paper first considers a brief history of the Taiwan question in the U.S.-China relationship and then outlines five major grand strategies—Liberal Internationalism, Deep Engagement, Conservative Primacy, Restraint, and Offshore Balancing—and attempts to distill each strategy’s policy prescription for the U.S. relationship with Taiwan. While conservative primacy and restraint seem to give clear answers—strong support for the Republic of China in the case of the former, and disengagement in the case of the latter—the three other strategies seemingly give less obvious recommendations. Given the widespread popularity of these three strategies in particular, it is little surprise then that there exists no clear consensus over what U.S. policy toward Taiwan should be.
International Law with Chinese Characteristics
As a victim of Western colonialism and imperialism in the 19th and 20th centuries under “unequal treaties” and “universal” international law, China has—especially since the founding of the People’s Republic in 1949—felt little obligation to faithfully comply with international law for any reason other than self-interest. Whether denouncing it as bourgeois in the early Cold War or disregarding an international law of the sea tribunal’s adverse decision in 2016, the People’s Republic of China has often shown a conflicted loyalty to a system of law it views as foreign. While China did join other developing nations in seeking to create a new system of international law in the 1950’s based on the Five Principles of Peaceful Coexistence, China has recently shown that as a Great Power it is willing to break even these purportedly key fundamentals of international law when it suites its interests. Thus, for the People’s Republic of China, international law is merely the continuation of international politics by other means.