The amount of control that was created though bureaucracy in the 18th dynasty was amazing. Thutmose III had several military victories that extended the boarders of the country substantially. He expanded largely to the north, conquering Palestine and Syria and putting them both under Egyptian control. This is often just the event that signals the end of an empire. It becomes increasingly difficult to control and rule over lands that are, largely, outside of the empire. Furthermore, the people are most likely speaking different languages, worshiping different gods, keeping different traditions and rituals; in short, the people are not homogenous and therefore are not easy to rule and control.
However, the 18th dynasty did a pretty good job of controlling their entire empire through several means. First, they had many different offices and representatives to look after different sections of the bureaucracy; governors, mayors, viziers, overseers, and priests. These people were responsible for many of the civil operations and organization which took a large burden off of the Pharaoh. Other traditions that were done to keep the peace with conquered areas were trade and marriage. If the Pharaoh is married to your daughter, you are less likely to go against or attack Egypt. Likewise, if you were giving a luxury good, or traded grain during a drought, you would think twice about any kind of hostility.
I also found it interesting that there was a separate police force. I would imagine that this was very important. The army of any country is trained to operate outside of the country, to extend the country and fight against the enemy. The police force, on the other hand, is trained to keep the peace inside of a country, to serve the people and keep them safe from internal harm. This is an important distinction because if you allow the army to police the people of a country, the people can become the enemy. This would probably result in a general loss of positive public opinion about the bureaucratic institutions.
~Cristina M. Cao