Read across enough conflicts and the same machinery reappears. Here are eleven deep engines of protracted human conflict in four families, and the sixteen cases they drive — not a checklist but a set of lenses, because no real conflict runs on a single engine. Open an engine to see which conflicts it powers; open a case to see which engines converge in it; follow the threads out to where the same force runs in the epic, in strategy, and on the ledger. The one claim underneath: enmity is not fated. It is made — and what is made can be unmade.