Egypt and the people of the Middle East were protected by the desert as can be seen in the lack of attempts from foreign forces for invasion.
Ancient Egypt and the people of the Middle East, primarily Mesopotamia, had several advantages when it came to development and security. The people living in these places were living along the banks of the large rivers, such as:Nile RiverTigrisEuphrates
These rivers provided fertile deposits, water for drinking and usage, means of transport and traveling, thus the people of this places had excellent basis to develop.
On the other hand, it seems that these people had almost no problems when it came to invading forces outside of the region. The prime reason for this was that the region is dominated by hot, harsh deserts. The people outside of this region didn't dear to cross the deserts and attack, as the chances were that the armies will either die during the crossing of the deserts, or they would be so damaged that they would not achieve anything.
Learn more about Ancient Egypt
In those regions there was no water and little rainfall it made it hard to settle and travel but that was what kept invaders out.