Game Theoretic Safeguards and Inspection Strategy Selection at an Enrichment Facility

Efforts by the International Atomic Energy Agency (IAEA) to improve efficiency in the face of a growing workload and stagnant budget highlight the utility of proliferation pathway analysis for informing safeguarding strategy. Proliferation strategies for a state depend on resources, capabilities and intent, making these characteristics vital considerations in a meaningful proliferation pathway analysis. This work uses a game theoretic computational tool that selects optimal inspector and proliferator strategies at an enrichment facility to explore the relationship between state characteristics and optimal proliferation strategy. The model couples a game theoretic optimizer to an enrichment plant simulation model to output an ideal inspector strategy and proliferator strategy for a given inspector resource level, as well as outputting an overall detection probability for the inspector-proliferator strategy pair. Payoffs to the players are the overall detection probability weighted by the quality and quantity of material the proliferator obtains. Varying the weighting scheme used to quantify material attractiveness serves as a proxy for varying state capability and characteristics by effectively changing the “value” the proliferator places on different types of material. For example, a state with clandestine enrichment capacity would value low-enriched uranium (LEU) much more highly than a state with no undeclared facilities, for which LEU is essentially worthless. Two types of attackers are modeled: (1) a “breakout-willing” attacker, who is willing to accept certain detection in the pursuit of large quantities of high-value material; and (2) a “risk-averse” attacker, who desires high-value material but will never accept certain detection when viable alternatives exist. Optimal inspector and proliferator strategiesfor both types of attackers are presented and differences in strategy based on state characteristics are highlighted. Conclusions are drawn about the relationship between state capability, vulnerable proliferation pathways, and efficient inspection strategies.