In The Dark Knight Rises, at the end of the movie Talia said, it was her father's dream to destroy Gotham city, and I accept that any daughter who was in that situation will definitely think to destroy Gotham to fulfill her father's dream.
But, I don't understand why does Bane want to fulfill the dream of Ra's al Ghul?
He was expelled from the League of Shadows by Ra's al Ghul. So, any man who was in that position would definitely have furious anger over Ra's al Ghul and take vengence. But Bane didn't do that, despite his ex-communication from the League of Shadows why would he want to work for Ra's al Ghul's dream? Unless it is because he's in love with Talia?