Stage 2: 71 Buildings

Elliot races to protect the Manhattan records building and believes he has stopped Stage 2, only to learn that the Dark Army bombed 71 distributed E Corp facilities instead, killing thousands.

The defense succeeds inside the assumed threat boundary while the adversary changes the scope and attacks every unmodeled copy. Local assurance is not system assurance when capabilities and targets are distributed.

The scope expansion is deliberate terrorism rather than accidental goal generalization, so the closest lesson is adversarial threat modeling and defense in depth.