The East China Sea (ECS) is one of the region’s most significant and oft-times under-addressed potential flashpoints. In this article we take a holistic approach and reexamine the recent actions of East Asia’s two most significant powers, China and Japan, in relation to this important body of maritime space, as well as those of the United States (US), as the incumbent regional hegemon. Specifically, we examine the efficacy of each. This highlights a dynamism in Chinese actions, as well as elucidating how the US and Japan have come to adopt policies that are of dubious efficacy as a means of alleviating or nullifying the escalation of unwanted tensions across the ECS. In so doing, we draw upon two key concepts, immobilism and confirmation bias, that help us to understand why the US and Japan are failing to achieve their assumed objectives of regional stability and the maintenance of the status quo. Ultimately, we argue that a combination of immobilism and confirmation bias in American and Japanese foreign policy, in response to the greater dynamism and adaptability of regional great powers such as China, has led to latent changes in the status quo that risk undermining stability across the ECS.