In accepting the Academy Award for Best Documentary Feature on Sunday night. Laura Poitras focused, as always, on the significance of transparency and visibility. As the film she made with Glenn Greenwald and Ed Snowden reveals, such democratic ideals remain at risk by the American government’s activities and attitudes. For all the daunting information Citizenfour reveals it asks you not only to see, but also to take responsible for what you see. Sometimes, the film offers long, nearly meditative takes of exteriors, the Hong Kong hotel from afar, implacably shiny, or distant views of dully thunk-thunking machinery at a new NSA data collection facility under construction in Bluffsdale, Utah, and near film’s end, a long shot of a kitchen window, showing Snowden and his partner Lindsay Mills, in their for-now home in Moscow, quiet, ordinary, perfectly framed.