This article identifies psychological, cultural, and organizational factors that drive optimism about emerging military technologies. Psychological influences include bounded rationality, cognitive biases (like the planning fallacy and confirmation bias), and motivated reasoning. Culturally, the US military’s “can-do” ethos and historical narratives about technology’s role in victory reinforce belief in technological solutions. Organizationally, interservice competition and strategic misrepresentation by program managers seeking resources amplify optimistic projections. All of these factors combine to contribute to technological optimism in US military acquisitions. Consistent with Amara’s Law, short-term impacts are overestimated, while long-term effects are underestimated. Similar patterns often emerge as defense technology entrepreneurs consider and present “new” technologies such as AI despite mixed results. Two policy imperatives are discussed: realistic assessment through independent reviews and phased investment, and decentralized experimentation enabling rapid local adaptation alongside traditional top-down innovation.