Theory of Strategic Bottleneck Migration First Passage, Constraint Substitution, and the Geometry of Resilience

Strategic resilience is commonly represented as stability, recovery, deterrent balance, or the aggregate amount of national capacity available under stress. These formulations are incomplete when survival depends on several finite constraints that can be exhausted at different rates. This article develops a theory of strategic bottleneck migration. If q_i*(p) denotes the critical disturbance associated with strategic constraint i, system tolerance is the lower envelope q_f*(p)=min_i q_i*(p). Strengthening the active constraint therefore improves resilience only until another constraint becomes limiting, producing bottleneck substitution. Pairwise equality of critical-disturbance surfaces defines mechanism-switch manifolds, and their displacement under parameter change yields a bottleneck migration law governed by differential rather than absolute sensitivity. For two operative constraints, the system admits the local normal form q_f*=Q-|G|/2, where Q measures common resilience level and G determines bottleneck selection. This decomposition separates capacity, selection, and transmission effects and yields a local adverse-substitution criterion, |G_r|>2|Q_r|, under which an intervention beneficial in one bottleneck regime becomes harmful in another. A nonlinear five-state strategic-resilience model illustrates the theory under compound shock, industrial reconstitution, finite command authority, persistent exposure, and command delay. The central result is that a strategic system may remain dynamically stable while its operative bottleneck migrates and its marginal susceptibility to additional stress changes sharply. Strategic resilience is therefore better understood as the evolving lower envelope of competing finite constraints than as a single stock of capacity.