Retaliate for justice!
Its late to start from the first step! If a society has already got preparation and sufficiency, it can welcome the promised Mahdi (hgr). Otherwise, the people will behave like what the formers did with prophets( pbu th) and saint people (ʾawliyāʾ) in history!
That’s why Amīr al-Mu’minīn; Ali ibn Abi Talib(pbuh) could not root out the devil, during short period of his government with those: divine power, divine science, volition power, the beauties and shinning in his honorable character. While it had been recommended a lot by prophet Muhammad(pbuh)!