India's intervention in Pakistan was purely strategic. It got the opportunity to exercise its power in the region. India being the more 'affluent' part of former India could exercise such right. The problem was no one analysed or came up with a solution on how to solve the Pakistan issue. But then thats common of South Asian politics. No country benefits from partition, socially, politically, economically the country is always left behind in the race of 'modernisation'.
Was India right to intervene? Well, anyone who saw what was happening in the genocide should have felt the obligation to stop it and resolve it or stall it if thats not possible. But when India comes into question you can't help think of the ulterior motives. The propaganda that followed. Glorifying Indira Gandhi's role, when really she was a really bad politician. She could relate to her people, arouse interests, win elections, but thats about it. Implementation and planning? not her forte unliker her fatehr.