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