A short summary of the history of Islam.
Islam has no history whatsoever of consensual rule or rotation in office. The caliph, sultan or emir is an autocrat who must put down other ambitious men to maintain his rule or even stay alive.
This fairly obviously forces other competent and/or ambitious men to plot against him to take power or even just in self-defense.
It's a major reason we really shouldn't worry about the Muslim world combining to attack the West. They'll always be too busy fighting each other.
You just can’t get good help these days.
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