India all along had a plan to break Pakistan. They used Mujib and Awami League to finish their job, they are still using Awami League.
Bihari's and other migrants (many of whom were Shia) tried to rule over East Pakistan with help of West Pakistan, a land that gave them refuge and welcomed them.
West Pakistan did some unfairness.
It was a skillful game played by Indians and its agent Awami League to instigate the civil war.
Just look at this forum. These Indian posters are not professional RAW agents, but if they can run blatant propaganda like this, imagine what the real professionals can do. They are masters of deception. They will take advantage of people's integrity and honesty to achieve their agenda.
This site, if nothing else is a good opportunity for us Bangladeshi's, Pakistani's, the rest of Muslim world and the world in general to study the character of Indian people and their propensities. What makes them tick and what makes them behave the way they do. They are delusional in a way, but they know their goal and they try to reach their goal their own way. 1971 was a great success for them and a great failure for both Pakistan and Bangladesh, not because we should not have separated, I believe eventually we could have separated, but we could do it amicably without the bitter civil war and the killings that took place.
And this killing was the handi work of Indira Gandhi and her RAW, who set up a true Agartala conspiracy, that catapulted Mujib and made him into a national leader, who then proceeded to win election in 1970. West Pakistan did not want to give power to a known traitor, but this was the only way they could avoid the civil war. Indian special forces moved in with AL agents and started killing Bihari's and to stop this killing PA started operation searchlight. Indira and her RAW set a trap for PA and PA stepped right into it.