Imam Ali bin Abi Talib assumed the caliphate in exceptional circumstances; when strife was sweeping the lands of Islam, and the blood of its caliph was spilled on its soil. Ali had many grave tasks that could not be postponed, the most dangerous of which was retribution for the killers of Uthman. However, Imam Ali saw the need to wait until he could establish his control over the state. As for Muawiyah bin Abi Sufyan and those who supported him, they wanted quick retribution. This was the beginning of the strife that claimed the lives of the best of Muslims, and the system of government changed from consultation to inheritance. The Shiites - supporters of Ali bin Abi Talib - and the Kharijites - his opponents - emerged as political parties, before taking on a social and religious aspect. However, the most painful result is that many of the calamities that are sweeping Muslims today trace their roots back to that strife, the embers of which are still burning to this day.
