He showed that numbers do not count and a handful of persons...
He showed that numbers do not count and a handful of persons, standing up to oppression at the cost of their lives, do in fact represent truth, justice, independence, and freedom. He showed that truth is irrepressible, eternal, and would manifest itself even from the trampled and lifeless bodies of the martyr. Their death is not defeat but is in fact the victory of truth, righteousness, justice, and the very spirit of freedom of mankind.
In as much as its other aspects, the uniqueness of Karbala extends even to its pathos. There is not a single human relationship that was left out from the list of martyrs. The relationship of the patriarch and his family, between the leader and his followers, parent and child, newly wedded husband and wife, between siblings, between cousins and children of cousins, bond between friends, master and servant, rider and steed etc., were all successfully put to test.
Historians, normally, are patronized by the winning party that assumes power and write the chronicles of the victorious. History may also record a few instances of individual valor of some opponent, but popular Historians never espouse the cause of the vanquished. Karbala is unique in this respect also.
Without exception, every chronicler records the justness of Imam Husayn’s cause, the cruel and unjust abuse of his dead body and the torment that the remaining members of his family and friends, particularly the widows and orphans suffered after the tragedy. Any historian attempting to eulogize the cause of the defeated forces would be branded a traitor. Such historians and their records would be, mercilessly burnt and put out of circulation.
However, at and after Karbala, the atrocities were so open and rampant that Yazid and his evil advisors, despite their tyrannical suppression and torture had no means or courage to prevent the tragedy of Karbala being related, recorded, repeated, and passed on to posterity.
In his speeches, letters, and discussions Imam Husayn (a.s.) made it clear that he was leaving Medina only in response to the call of the Kufians who had written thousands of letters and sent hundreds of emissaries complaining that they had no Imam to guide them in matters of faith and that, as the Imam , it was incumbent upon Husayn (a.s.) to hurry to their guidance.
Their complaint against Mu’awiya first, and later against Yazid, was not so much regarding the physical or monetary suffering but against the willful distortion of the principles of Islam.