This essay examines key trends in war and posthumanism, from the early rise and recent revitalization of the idea of autonomous war machines, and the way the cyborg body acted metonymically for the unwilling soldier sent to Vietnam. The majority of military science fiction has backed away from the prospect of transhuman war, and even popular war franchises like Iron Man (comics and film) maintain that humans must and will be at the center of combat. The insistence on human agency in war flies directly in the face of US military policy, driven by the Revolution in Military Affairs. Just as war is being fought at ever greater removes by drones and autonomous weapons, popular military science fiction has retreated to representing wars whose technologies and strategies date from the mid-twentieth rather than mid-twenty-first century. Using fiction, film, and comic texts, this essay argues that maintaining human agency is crucial to the United States’s ongoing concept of itself as a frontier country advanced by determined pilgrims.