he conquest of Nubia was not just a response to incursions by Nubians, but made economic sense by bringing the rich Nubian gold mines and the overland routes to Kush and Punt under Egyptian authority.
The Sinai desert was important for its copper and gem stone mines, and its trade routes through Arabia to the Horn of Africa, and later to Persia and India.
Retenu (Canaan and Syria) was a buffer region against Asiatic attacks, but also a crossroads of trading routes and there is evidence of royal trade and exchange in the form of Egyptian style clay cylinder seal impressions and serekh signs from as early as Narmer's reign.