Hallucinating the Firing Solution:
Large Language Models in Autonomous Weapons and the Coming Fratricide Incident Proceedings U.S. Naval Institute | Analysis & Commentary Vol. 152 | June 2026 Technology & Weapons Systems Autonomous Systems & Artificial Intelligence The Department of Defense is integrating Large Language Models into autonomous weapons architectures faster than testing methodology exists to validate them. The specific failure modes of LLMs — hallucination, non-determinism, helpfulness-driven completion of missing data, and prompt injection vulnerability — are not engineering defects that will be resolved through iteration. They are properties of the architecture. A fratricide incident is not a risk to be managed. It is a timeline to be shortened or lengthened by the decisions made in the next eighteen months. Stephen L. Pendergast, IEEE Sr. Member (Ret.) | Senior ...