Yes, it was a REAL insurgency by East Pakistanis, unlike all those fake insurgencies Pakistan has been trying to cause unsuccessfully in Indian Punjab and Kashmir for decades.
Funny thing, how history is tainted.
When the issues related to East Pakistan started, they were the majority with about 53% of the population. But, in the paradigm of Pakistan, they have been considered as minority, insurgents.
I say, if they are majority in terms of population then they should be considered the nationalists and West Pakistan being the separatists.
Muslim League was defeated badly in the 1937 elections, after which the decision of creating a separate state came into being. Incidentally, in that election, Muslim League had won highest number of seats in Bengal, around 35-37, but only 1 in Punjab, while Congress had won 18 or 19. So, clearly again, Bengal was the majority and Punjab was the minority.
Ironical fact, when people of Pakistan had it's first full-fledged democratic election, in 1971, the majority was routed by the minority.
And then India gets the blame..
-)) screwed Pakistan!
