Stephen Van Evera explicitly sets out to accomplish twotasks. The first is to present a set of five hypotheses on thecauses of war grounded in "misperceptive fine-grained struc-tural realism" (p. 11). He lists (1) false optimism about theoutcome of a future war, (2) perceived first-mover advan-tages, (3) opening and closing windows of opportunity andvulnerability, (4) cumulativity of resources, and (5) beliefsabout the offense-defense balance. He then develops 23related hypotheses. The second task is to test some of themajor hypotheses (the second, third, and fifth) against a smallset of cases. He succeeds at the first task but is not sosuccessful at the latter. He also briefly speculates on theeffects of the "nuclear revolution."