What determines a state’s grand strategy in space? Through detailed case studies of states with independent orbital launch capability, this study reveals that a state’s rational assessment of its threat environment and power distribution vis-à-vis other states compel it to adopt strategies of defense, offense, or a balanced approach. Gaining insight into the motivations driving the adoption of specific strategies in space is essential for guiding policymakers in crafting effective strategies to address and manage future challenges in space. Moreover, detailing the methods and motivations behind states’ exploitation of space for their security interests enriches the broader literature on state behavior and security studies. Space strategy has become increasingly relevant as states intensify their efforts to leverage space for national security interests. Since 2005, China has tested eight direct-ascent anti-satellite (ASAT) weapons and, in 2024, abstained from a UN Security Council resolution banning nuclear weapons in orbit. If such devices were deployed and utilized against U.S. assets in space, it would inflict substantial damage on the U.S.’s space infrastructure. Counterspace attacks could cripple critical systems such as GPS, global communications networks, and intelligence capabilities, thereby severely impairing the nation’s ability to conduct military operations, monitor threats, and maintain space situational awareness. The deactivation of GPS alone could result in staggering economic losses, estimated at approximately $1 billion per day for the U.S. economy. Meanwhile, the U.S. has adopted a defensive posture by explicitly supporting a ban on direct-ascent ASAT weapons at the UN, investing in constellational satellites, and halting further testing of direct-ascent ASAT weapons. What explains these variations in tactics that states deploy to protect their national security interests in space?