The elaborate military organization and technology described in the preceding chapter were well suited for offensive purposes, but it was strategic problems of defense and internal security that were overriding concerns in the Sokoto Caliphate throughout the nineteenth century. Several conditions contributed to the emirates' preoccupation with these problems. First, as we have already observed, the jihad was an ongoing process of conquest and consolidation rather than a completed event, especially in the non-Hausa areas. Second, the enormous geographical extent of the caliphate made it impossible to defend its domain by means of a centralized security organization. Sokoto and Gwandu, the dual capitals of the caliphate, were located in the western part, leaving the eastern emirates beyond the protective perimeter of any defensive arrangement that could have been provided from the capitals. In addition, the mobilization and movement of territorial reserve armies of cavalry and foot soldiers, accompanied by spare mounts and a baggage train of human porters plus camels, oxen, and donkeys, was a relatively involved and slow process. Furthermore, as campaigns were generally undertaken in the dry season, the route of march was tied to requirements of food and water for the livestock and soldiers. Finally, the absence of standing armies in Sokoto or the constituent emirates of the caliphate contributed toward the development of parochial and ad hoc security arrangements. It is in the context of these limiting conditions imposed by territorial expanse, means of transportation and communication, and military organization, that the strategic posture of the Sokoto Caliphate must be examined.