Ideally, i guess, in some mental models, we'd love to have some sort of super powerful system that can compute a global utility function that considers second (and third, etc) order effects accurately enough to plan out actions that maximize the global utility (without violating ethical norms) until we are immortal and have unlimited energy resources and ability to manipulate matter.
In practice, we instead have centers that focus on first-order effects and who advocate for their position (from an authority based on scientific knowledge, and preparation for emergencies) which are then evaluated and mixed with other centers by political leaders to incorporate the best attempt at considering second and further effects.
Everybody has a different utilitarian model and we don't have enough data or algorithms to predict second or third order effects (we usually fall back on "wisdom" from prior experience).