The United States must ensure that its military can adapt to an evolving threat environment to maintain its relative advantage vis-à-vis potential adversaries. Should the U.S. tackle this task unilaterally, however, the perception of relative U.S. decline will only aggravate uncertainties in Japan and South Korea about U.S. defense commitments – and in China about U.S. intentions in Asia. The views of U.S. allies and partners are shaped in part by the debate in the United States about future defense technology and concepts, a debate that is perceived to be more thinking-aloud than substantial policy. Lost in Translation? U.S. Defense Innovation and Northeast Asia examines Northeast Asian perceptions of the risks posed by disruptive technologies in the military sphere and recommends a series of policy steps to minimize these risks.