Diplomacy and defense have always gone hand-in-hand, and space is no exception. Space has become a fundamental part of daily life and of U.S. national security, ranging from command and control to intelligence and navigation. As the uses of space grow in significance, so too has the question of how to keep space systems safe and secure, and one of the potential answers to that question is to fill in gaps in norms of responsible behavior for space. What may seem like a relatively niche topic actually supports a broad swath of U.S. strategic objectives and has become a central line of effort in protecting national security interests in the space domain. America’s space norm efforts have moved beyond broad public statements and into national defense policies and strategies.

In response, some commentators have questioned the value of space norms for defense and deterrence. After all, a norm cannot prevent a determined adversary from taking aggressive actions, nor can it intercept a missile or shield a satellite from attack. Criticisms include allegations that nonbinding norms are relatively toothless, that they can unnecessarily constrain U.S. behavior, or that bad actors will simply ignore norms and do what they want anyway. There is some validity in each of these critiques. Yet, norms do play a crucial role in space security, as they have in other domains for centuries.