When Malicious Actors Take Over Your Subsystems

On April 14, 2025, David Hetherington and I presented to INCOSE Canada on: When Malicious Actors Control Your Subsystems: A Systems Engineering Approach to Functional Perseverance. The message was blunt: cyber compromise is now a design condition, not an edge case. Using System-Theoretic Process Analysis and System Dynamics, we showed how systems can be engineered to remain fail-operational rather than fail-safe through distributed control, diverse redundancy, adaptive recovery, and informed trade-offs between cost and resilience. Bottom line: security is not a bolt-on feature. If your system must keep working under attack, security has to be engineered in from the start.