No One Wins in Nuclear War: A Social Simulation of Military Decision-making
2026-08-03 • Computers and Society
Computers and SocietyArtificial IntelligenceComputation and LanguageMultiagent Systems
AI summaryⓘ
The authors created WOPR, a tool that simulates how groups make important decisions using a rules-based system. They tested it using a known card game called Nuclear War to make sure the rules work correctly. Unlike other simulations, WOPR can track decisions step-by-step and allows secret communication between groups. It can also run with different social simulation setups, and in WOPR, groups are controlled by multiple agents working together. The authors have shared all their code and examples online for others to use.
social simulationrules enginewargamesNuclear War card gamereplay validationprivate communicationagent-based modelingConcordia frameworkcommand-and-controlstrategic decision-making
Authors
Glenn Matlin, Isaac Song, Anthony Wen-Ming Zang, Mark Riedl
Abstract
WOPR is a social-simulation environment for studying how organizations make high-stakes decisions, built on a deterministic, replay-validated rules engine and using wargames as the vehicle. We instantiate it first with the published card game Nuclear War, traced against its published rules. We start with military decision-making because of its safety implications and because it needs further study, but the design is not specific to it: the decision-point contract that exposes the engine to agents is reusable across verifiable rule systems. Existing social-simulation work emphasizes persona fidelity and synthetic opinion, but lacks a verifiable rules engine with replay-checkable mechanics and private-channel negotiation. WOPR supplies that engine, and its contract makes every strategic choice an explicit agent decision. The method is agnostic to social-simulation frameworks; we adopt Concordia as the default harness for driving the game. On the same engine, WOPR layers a four-rung press ladder from silence to private single-recipient channels with structured commitments, and instantiates each faction as a collective command-and-control system rather than a single agent. We make all code, example configurations, and replay data publicly available at https://github.com/eilab-gt/wopr.