His characters are victims of their place and time. In Crouching Tiger Chow Yun Fat and Michele Yeoh are stifled by the code they live by. It's the same with the two boys in Brokeback Mountain. We, the audience, can see there's an escape route- that there's nothing absolute about the values that imprison them; they can't.
Lee creates a world. He deconstructs it. You see how it works and how it fails. Running under everything is the implication that people can escape their destiny if they choose. The walls that hem us in aren't real but man-made. There's something else out there, another reality. All we have to do is go through the gap.
Out of the multiplex into the street.
Zhang Ziyi takes a dive from the walls of the mountaintop fastness, Tobey Maguire walks away from the war, Heath Ledger decides he will go to his daughter's wedding after all.