There were many causes of the Mahabharat war.
I have tried to write down the reasons from the point of view of some of its main characters.
* Though born blind, Dhritrastra was desperate to rule. His sons’ victory in this war would ensure that no one would be left to challenge his right to the Kuru throne.
* He let Pandu rule under duress. He was unwilling to pass the crown to his nephews while his own sons were still alive.
* Dhritrastra was an indulgent father and wanted to live “his life” through Dhuryodhan.
* Dhritrastra wanted nothing to stand between his son(s) and their wishes – whatever those wishes maybe.
* So desperate was he to rule as a king, he was unwilling to let go of the throne even after the war ! Even after all his sons and grandsons were dead, the “king” could not let go of the crown !
* Duryodhan and his brothers believed that as grandsons of the eldest wife of Vichitravirya, they deserved to inherit the throne. It wasn’t their fault that their father was blind ! Why should they be deprived of the kingdom because of their father’s disability ?
* As the current incumbent of the throne, they believed their father should be able to pass the kingdom on to them.
* Having deprived the Pandavas of their kingdom during the dice game, they believed it to was right for them to keep their cousins out of power by any means – including this war.
* Might is right. Having conquered their rival, by means fair or foul, it was their right to keep whatever they had amassed at whatever cost.
* Having the likes of Bhishma, Drona and Karna on their side, they felt they could not loose the war. There was no reason for them to fear the Pandavas and so they could deprive Pandavas of their rights at will.
* As the sons of Pandu, they felt they were the rightful heirs to the throne. Their uncle Dhritarastra was a regent in their minority and should have passed the throne to them.
* Public insult to their wife Draupadi was unforgivable, especially as Kauravas were unrepentant in their attempt to denude her in public. Just as the insult was public, its counter – the war – had to be just as public.
* They had been denied their rightful share for long enough. Now for themselves as well as their children, they had to press for their inheritance to make sure they were not cut off forever.
* Their patience had now worn thin and they were no longer hopeful of a negotiated settlement allowing them a fair share in the ancestral kingdom.
* There was no other recourse but to fight and press for their “rights” as princes and heirs of the Kuru dynasty.
* War was inevitable as all their attempts at peace, including the last offer of settling for five towns for the five brothers, were rejected by the Kauravas.
* Kauravas had harassed them all their life. It was now pay-back time.
* There is nothing more dangerous in this world than a woman spurned. Drupadi had been humiliated and insulted in the presence of kings, courtiers and commoners after the dice game. As a princess of Panchal, Kuru empress and a wife of the Pandavas and more importantly as a woman, she was smarting under the insults from the dice game. Honour and pride demanded that those who were guilty of her insult, should be punished. This war was the only thing that would wipe away her shame and sadness.
* Those who had dared dragged her into court, or suggested she take other men as her lovers / masters, or made sexual advances at her, had to be publically punished to protect ALL married women in the future.
* Good had to win, otherwise mankind would not have any incentive to be good.
* Letting Kauravas win or get away without punishment, would be disastrous for humanity as it would lead to breakdown of social order. No one would be safe – women, law-abiding citizens, weak people etc.
* Having personally tried all social, political, ethical, moral and spiritual arguments to help the cousins live in peaceful cooperation, this war was judged to be inevitable consequence of Kaurava implacable entrenchment of their views.
* Kauravas were unwilling to share their paternal kingdom and this war was the only recourse for natural justice to be delivered to the Pandavas.
Durpada, Shikhandi and Dhritadhyman :-
*Vengeance is a dish best served cold.
*Loss of half of Panchal to Drona had been hard on the Panchal royal family’s sense of honour. This war was their chance to regain and reunite their kingdom.
*Drupadi’s insult in the Kuru court was as much an insult to the Pandavas as to the Panchalas. All those who were responsible for this shameful episode had to be punished and killed in the war to restore the honour of Panchala clan.
* Ever since he gate-crashed the graduation ceremony of the Kuru princes, Karna despised Pandavas for their perceived lack of respect for his prowess. He wanted to prove that he was superior to them in every respect.
* This battle would help prove Karna’s prowess and prove to the world – once and for all – that he was superior to Arjun in archery and other arts of war.
* Bhishma, Drona, Krupacharya had always derided Karna for not being “good enough to fight with Arjun”. This war was his opportunity to prove them all wrong.
* Karna hated Drupadi for having rejected him during her swayamvar. He wanted to repay her insult for insults at every opportunity. Depriving her of her husbands in a war was an opportunity too good to miss.
* Embittered by life long hate for the Pandavas, Karna could not befriend them even when he found out they were his own brothers. He told his mother Kunti that the war was his cherished chance to fight against Arjun.
* Ever since Duryodhan crowned him “king of Anga” Karna felt beholden to Duryodhan. In a moment of utter gratitude, he swore a life long allegiance. He vowed to support Duryodhan through thick and thin. If need be, he was willing to repay Duryodhan for his largesses with his own life. This war was his chance to pay Duryodhan back for his friendship.
* This war would avenge the perceived insult of his beautiful sister having to marry a blind man ! Shakuni never recognised the fact that marrying Dhritarastra allowed his sister to be a queen of a large kingdom. Had his sister married Pandu, she would have been a widow for the best part of her life !
* Desperate to please and indulge his nephews, Shakuni was willing to do anything – anything – to ensure that his nephews got everything they wanted.
* He had been trying to get rid of Pandavas for years. This war was his way of getting rid of Pandavas once and for all.