Yeah, the British just packed up and left by themselves ? Or do you forget that the independence movement started from Bengal and not from some Northern dusty badlands.
British came to Bengal first because we were the economic and cultural centre of the subcontinent, you control Bengal, you can easily exert control on the rest of the region.
The seeds of independence from Hindu rule was sown in 1905 through the partition of Bengal, which was the catalyst that led to other Muslims elsewhere who were until then sucking their thumbs to wake up and stand against the Brahmin menace.
They controlled us using artificially induced famines, do not pretend to be daft and ignorant unless it's your default state.
Blind nationalism is a hell of a drug, read history sometimes and not from pakistani text books.