Abstract
The convergence of three quantum computing milestones in twelve months has compressed the post-quantum cryptography (PQC) migration timeline from a next-decade concern to a present-day operational imperative. A model-adjudicated analytical wargame formalizes PQC migration decisions across eight military C4ISR systems under Bayesian uncertainty about the emergence of a cryptanalytically relevant quantum computer. The wargame spans 18 decision epochs (2026-2034), employing DEVS coupled models derived via Wymore morphism from a SysML v2 specification and adjudicated by a Modern Wargaming Decision Theory (MWDT) Knowledge-Gradient policy that quantifies the expected information value of each migration choice.
Four scenario branches produce differentiated outcomes across all metrics. The central finding: migration sequencing determines Agile Combat Employment (ACE) operational trust more than migration speed. Breadth-first protection of five systems achieves 61% ACE trust; depth-first commitment to a 72-month Link-16 hardware replacement protects three systems at 54%. The Trust Now Forge Later (TNFL) attack---quantum-forged digital signatures injected into decentralized C2---collapses trust five decision epochs earlier than any other scenario, exposing a vulnerability unaddressed by current CNSA 2.0 signature migration guidance.
AI-driven acceleration of quantum error correction---from AlphaQubit's neural decoders to NVIDIA Ising's GPU-accelerated QEC---is compressing the timeline toward a cryptanalytically relevant quantum computer, though no calibrated estimate of this compression yet exists. An agentic AI research and validation pipeline with 384-dimensional vector embeddings ensures every claim in this paper traces to verified source data. All scenario parameters trace from domain ontology through requirements and SysML specification to DEVS runtime parameters. The Knowledge-Gradient policy provides a quantitative baseline for after-action review, measuring divergence between decision-theoretic optimality and operational judgment across all 18 decision epochs.
PALLC and the work
Our mission-engineering and simulation tooling connected domain ontology and requirements to SysML v2 specifications, executable DEVS models and scenario evidence. A decision-theoretic policy evaluated the information value of available actions, supporting repeatable comparisons and structured after-action review. The workflow gives teams a traceable basis for examining modernization priorities and the consequences of competing migration strategies.