A democratic or a republican form of government just does not work in Muslim countries. There has never been one, so why would anyone think it can work now.
Self-government can only work among virtuous people. The reason the Roman Republic was replaced by the Empire is that the people had become corrupted, and were no longer fit for self-rule.
The Egyptians have NEVER known the level of virtue needed for self-rule. It is not part of their culture, and has never been part of it. They have ALWAYS been ruled over.