Through the Oculus display, I saw nodes grouped by rule. These included hard rules, like an impassable boundary where the option couldn't take place. Frank Pound, the Plan X program manager, explained that such rules could include legal barriers. For example, "a senior officer could say that, for this mission and because of treaties, we can't use any routers in France," and so the PlanX display would exclude them, making tangible limits devised under law. Here rules just won't be built in during a mission, they'll be tested, first, in a wargame simulation, so the team can know if the mission is possible with the given constraints.