This chapter examines wars, attempts to create regional order, and how these have impacted on the structure of the Middle East regional system, which, in turn, has reshaped the states that make it up. The search for solutions to regional conflict, for a basis on which to create a secure order, has been ongoing since the founding of the Middle East states system. However, each of the major attempts to build regional order proved defective, in varying degrees ameliorating or containing conflict but also either failing to deal with its roots or sometimes actually exacerbating it. War has originated in domestic level dissatisfaction shaped by these struggles which, when institutionalised in rival states, is expressed in conflict at the states system level, frequently over territory. Everywhere, in a region afflicted with irredentism, domestic politics encourages nationalist outbidding.