There are movies that are long and fail to hold your attention. But Zero Dark Thirty is not really that long (just over 2 and half hours) - it feels much longer; but still holds your attention throughout. It is an uncomfortable movie to watch; especially the much talked about torture scenes. But there is an element of relentless pursuit - and only towards the end do you realise that this movie covered events spanning a decade.
It is a movie; not meant to be a documentary - but in many ways, this will be seen as a historical re-enactment. It is in that, the torture scenes become poignant - since there is a catch-22. To state that torture evidence was not useful, further extends the view that torture is barbaric and has no place in modern civilisation. To state that torture evidence was useful, and the result justifies the means; questions the very existence of treaties such as the Geneva convention - and any position of moral superiority. Ultimately the movie chooses the later - and like it or not - most people in the US seems to identify with the results more than the means.
It is a superbly acted and directed movie. The questions about torture has affected the movie's reap of rewards - but I do think it at least poses the right questions.