Establishment of justice requires a government led by justice seekers
Another lesson the belief in Mahdawiyyah and mid-Sha'ban celebrations [rejoicing the birth anniversary of Imam Mahdi (a.j.)] must give us is: the justice we are looking forward to-- justice established Imam Mahdi (a.j.) that is to fill the world-- is not achieved by simply preaching and giving advice. That is, the promised Mahdi of nations is not going to preach the oppressive powers to make them avoid oppression, avarice, hegemony and exploitation of other nations. By only giving advice, justice will never be established. Establishing justice, either at the global level --as will be done by the heir of the Prophets-- or in any area of the world, requires that just, benevolent individuals hold a powerful position and address the domineering powers with a language of power. It is impossible to advise those who are arrogant, due to their oppressive power. Only a language of sovereignty works for communicating with them... Those who favor justice, should equip themselves with power against domineering hegemonic powers who invade humans' rights. So you see, ever since the Islamic establishment was formed--that is, Islam gained the power of a big nation, and resources of a big country and government-- the enemies of Islam took the movement of Islam seriously and the supporters of Islam across the world became hopeful.