Carthage was more than a vital agricultural center, which the Byzantines spent massive efforts to recapture and retain. It was an excellent fortress on a promontory, extremely difficult for the land-based Arabs to take from the naval strength of the Byzantines. When the Arabs finally took the city in 698, it was after 50 years of conflict which had prevented the Arabs from capitalizing on their control of Egypt. Seizing the wheat fields of Carthage and Egypt finally gave the Arabs an irresistible advantage.

This is why the Arabs razed the city. This was a much more thorough job than the earlier Roman demolition of independent Carthage; the walls and buildings were torn down, the harbor filled with rubble, and the aqueducts and canals destroyed.

Nearby Tunis had many of the locational advantages of Carthage without the drawback of being an irrestistible fortress which would serve as a magnet for Roman attacks. The surviving population of Carthage was put to work hauling building stone from that city to jumpstart the growth of Tunis. Once Tunis was well-established only 15 kilometers away, there was never a compelling reason to redevelop Carthage.