If outer space becomes an active theater of war, the impact to daily life on earth would be substantial. Unintended consequences of attacks in space are hard to contain and are not always readily reversible — debris or radiation generating attacks render specific orbits unusable, not just for the duration of the war, but for the foreseeable future. With the loss of those orbits, our lives would be very different — accurate weather maps, overhead imagery, access to breaking international news, and navigation services that guide our cars, airplanes, and ships would all disappear. Even in the absence of catastrophic attacks, war in space would have a chilling effect on commercial uses. Deploying new capability in space is risky, and war would make it infinitely more so. Space entrepreneurship would grind to a halt, denying mankind capabilities we have yet to dream of.
In this dissertation, I use a game theoretic model of space war to examine how sentiments in multiple dimensions impact state decisions regarding whether to expand a ground war into the space domain. Key innovations of this model are a) the use of prospect theory in lieu of rational choice and b) the assumption of non-unitary actors with independent sentiments regarding different dimensions of national interests. I offer a new way to visualize and think about how sentiment impacts the ability to tailor a deterrence strategy to specific circumstances. These innovations enable a rich exploration of how space war might play out across a wide range of futures. Based on that exploration, I recommend specific steps spacefaring nations should take to robustly deter the expansion of wars into the space domain. My recommendations are applicable across a wide range of opponent capabilities and sentiments under both rational choice and prospect theory.