The Nile and the Euphrates

Around the year 4000 BC, a civilization appears on the side of the Nile river. The Egyptian Empire lasted more than 3000 years and was the first civilization in History that built great architectural and artistic works, also to create an organized central administration.
In parallel, in the area between the courses of the rivers Tigris and Euphrates, in Mesopotamia, state-cities arise (Sumer, Akkad, Susa, Ur, Babylon) that will compete on each other and develop an equally important cultural identity. To them we owe the first aphabet and the code of laws.
However, the development in both of them was very different. While in Egypt a great politic entity appear and was stable for thousands of years, Mesopotamia saw endless confrontations between its small state-cities, none of which managed to impose its hegemony permanently. What is the reason of this difference?

Two basins, two civilizations

Certainly, both river sides were very fertile. However, they were in a different manner.
The river Nile suffers periodic floods. It is necessary just a minimum human effort to take the maximum profit, guaranteeing also rich harvests with a great stability. The sides of the Tigris and the Euphrates, to begin with, are more mountainous and less favourable to agriculture. Moreover, harvests are not necessarily always good, but droughts and floods can sometimes happen. Thus, in order to take the maximum benefit of its potential, it was necessary for its population to build great dams and complex irrigation systems. Exactly, archaeological findings in Ancient Mesopotamie show the existence of this kind of works, while they are rare in Egypt.

Social consequences

In Egypt, food stability allowed a long prosperity and the establishment of an empire in which citizen miscontent was not frequent. This Empire was relatively stable for thousands of years, until its inactivity finally provoked its decadency. In Mesopotamia, on the contrary, the support of the community was necessary for the good operation of irrigation systems in difficult conditions, and in this context, the role of the city was fundamental to establish guarantees. Moreover, when bad harvests happened, was was frequent, usually provoked by disputes on territories or resources.

It is interesting how similar cases have repeated along History. Stability makes people open-minded, risking sometimes to lead to cultural sleeping. In difficult periods survivance instincts are more important, the people get isolated in their community, and show aggresive to external identities.