Imam Ali (a.s) advised Malik al-Ashtar when he appointed him governor of Egypt when he was the caliph of the Muslim Ummah as follows:
Surely, the virtuous are known by the reputation that Allah circulates for them through the tongues of His creatures. Therefore, the best collection with you should be the collection of good deeds. So, control your passions and check your heart from doing what is not lawful for you, because checking the heart means detaining it just half way between what it likes and dislikes.
Habituate your heart to mercy for the subjects and to affection and kindness for them. Do not stand over them like greedy beasts who feel it is enough to devour them, since they are of two kinds, either your brother in religion or one like you in creation. They will commit slips and encounter mistakes. They may act wrongly, willfully or by neglect. So, extend to them your forgiveness and pardon, in the same way as you would like Allah to extend His forgiveness and pardon to you, because you are over them and your responsible Commander (Imam) is over you while Allah is over him who has appointed you. He (Allah) has sought you to manage their affairs and has tried you through them.
Source: Nahjul Balagha
If this advice given by Imam to one of his governors about 1400 years ago was carried out without hesitation, what do you think this our current generation and its leaders should do to bring about positive change in our societies?