I thought planned or limited wars were against the rules for exactly this reason.
I think this is true...
Though, frankly, that would require that D'Hara go to war with Caerwyn, or Madina, or Barca, or Terran. War with Caerwyn or Madina is imaginable and not completely self-destructive. War with Barca or Terran would make no sense at all.
Honestly, again, this has a lot to do with D'Hara's geography. Its high urban density combined with controlled border corridors (narrow land routes with allies, long sea routes) renders it uniquely secure from external attack, uniquely dependent on external trade, uniquely unable to acquire sufficient domestic food supplies, and uniquely unable to engage in aggressive warfare. Code that makes a great deal of sense elsewhere will have disorienting effects on such a distortionary realm.