Over the past two decades, China’s People’s Liberation Army (PLA) has transformed itself from a large but antiquated force into a capable, modern military. Although China continues to lag behind the United States in terms of aggregate military hardware and operational skills, it has improved its capabilities relative to those of the United States in many critical areas. Moreover, China does not need to catch up fully to the United States to challenge the U.S. ability to conduct effective military operations near the Chinese mainland. Ensuring an adequate defense and deterrent capability in the face of these trends will require careful consideration of U.S. strategy, procurement priorities, and relations with regional allies. Much of the discussion about China’s military modernization in the United States has focused on new PLA weapon systems. There has been little comparative analysis of Chinese and U.S. military forces and developments—and even less rigorous analysis of how those inventories and systems would perform against each other in a potential conflict or how the balance of relative capabilities has evolved over time. This brief summarizes RAND Project AIR FORCE analysis that seeks to fill this gap. The research uses a set of “scorecards” to assess the relative capabilities of U.S. and Chinese forces in diverse types of conflict, at varying distances from the Chinese mainland, and at different points in time from 1996 to 2017. Based entirely on open sources, the scorecards provide a basis for deeper public discussion of how the balance of power in Asia has evolved and the challenges the United States can expect to face in the future. To be clear, the goal is to avoid war, which the authors do not anticipate and which would be disastrous for both China and the United States. The scenarios and the operational activities described here are not meant to signify either the likelihood of a future conflict or the course of events should one occur. Nor do they represent U.S. national or military policy with regard to whether or how such a war would be fought. Rather, this research provides an open-source assessment of trends that could affect U.S. defense and deterrence strategy and establishes a baseline for future analysis.