Public opinion and the politics of the killer robots debate

The possibility that today’s drones could become tomorrow’s killer robots has attracted the attention of people around the world. Scientists and business leaders, from Stephen Hawking to Elon Musk, recently signed a letter urging the world to ban autonomous weapons. Part of the argument against these systems is that they violate the public conscience provision of the Martens Clause due to public opposition, making them illegal under international law. What, however, does the US public think of these systems? Existing research suggests widespread US public opposition, but focused on support for autonomous weapons in a vacuum. This paper uses two survey experiments to test the conditions in which public opposition rises and falls. The results demonstrate that public opposition to autonomous weapons is contextual. Fear of other countries or non-state actors developing these weapons makes the public significantly more supportive of developing them. The public also becomes much more willing to actually use autonomous weapons when their use would protect US forces. Beyond contributing to ongoing academic debates about casualty aversion, the microfoundations of foreign policy, and weapon systems, these results suggest the need for modesty when making claims about how the public views new, unknown technologies such as autonomous weapons.