Therefore...
In divinely commissioned government, there is no place for personal aggrandizement. The yardstick of Allah’s Rule is neither power nor pelf of individuals but the one who administers and enforces the norms and Commands Revealed by Allah. No doubt, those who came to the caliphate were called Muslims. But the Islamic Rule does not mean that a person who has embraced Islam comes on the top to rue. But it is the implementation of the life style that the Prophet (a.s) had enunciated.
If anyone establishes rule contrary to those norms, then that is not an Islamic regime. Therefore, the rule of Yazid, Marwan, `Abd al-Malik and persons of that ilk cannot be called as Muslim rulers. In fact, they were the images of Heracles and Caesar in an Islamic environment! `Ali’s rule was truly Islamic. He had accepted the caliphate only on condition that no one should interfere in his running the administration exactly in accordance with the norms laid down by the Shari`ah of Islam.
Although his period was dominated by intrigue and troubles created by his enemies, that in his brief rule he presented an administration that was in accord with the style of governance of the Prophet (a.s) and implicitly followed the Commands of Allah. If he had not taken the reins of governance in his hands, people would have forgotten what is divinely commissioned government. Running the governance on the Islamic norms is something and acquiring power through politics is something else.
Amir al-Mu’minin’s entire life is a proof that every act of his was in accordance to the Commands of Allah. If he accepted the caliphate, he did it with the condition that it would be the divinely commissioned government and not personal rule. He gave real interpretation to “Who has not a partner in the kingdom, (17/111)” through his actions as the caliph.
If he were interested in personal aggrandizement, he would not have dismissed the functionaries of the previous regime against many well-meaning advisers.