It isn’t just the pacing Mann employs that helps build his constant tension, but also the ambiguous structuring of the film by which it’s never entirely certain which character – DeNiro’s McCauley or Pacino’s Hanna – is the protagonist, and which is the antagonist.
Is life a dream? Who knows? But I do know that 7 minutes and 36 seconds isn't nearly enough time to answer that question, so instead I focused on Richard Linklater's answer to that question.
When you talk about movies that have shaped cinema, I think that 'M' by Fritz Lang has to be in the conversation. Although it wasn't the first movie to use sound, it was the first to use it well.