Rational states weigh expected gains versus not attacking, not damage ratios

Evidence

But in neither case was such a simple yardstick appropriate. States do not decide to go to war on the basis of comparisons between how much they will suffer and how much harm will come to their adversaries. If decision makers are even minimally rational, they compare their estimates of the probable gains and losses of going to war with what the state expects the situation to be if it does not attack. Thus an aggressor could be deterred even if a state thought it could inflict more damage than it would receive or, in other circumstances, could attack even if it thought this balance was reversed. — John T. Jost and Jim Sidanius, Political Psychology, 2607

Categorization

• DEFINE: Clarifies the correct decision framework (expected-value comparison against status quo) versus the flawed symmetric-damage yardstick.
• XREF: Ties to rational choice and expected-utility models of war initiation (Fearon, Bueno de Mesquita); the asymmetric-deterrence point also connects to signaling and brinkmanship theory.