Let's face it: If the world were a happy place, we wouldn't need a United Nations, since the nations would already be united. But it isn't and they aren't, and the United Nations Association Film Festival spotlights documentaries from around the world on a variety of depressing topics — including (but not limited to) famine, racism, and homelessness. To add to the anxiety, this year's theme is "Running Out of Time." It's later than you think, people! One wrist-slasher on the docket is Dyanna Taylor'sDorothea Lange: Grab A Hunk Of Lightning, about the famous Depression-era photographer. (You've seen her Migrant Mother even if you don't realize it). Tonje Hessen Schei'sDroneis not about the underappreciated music genre, but about the flying robots that spy on and kill people from above. Movies with the titleIt Happened Hereare never about pleasant things — the last notable film by that name was Kevin Brownlow's 1965 faux-documentary about Nazis occupying wartime England — and Lisa F. Jackson's new film continues the trend. This It Happened Here examines the pervasiveness of sexual assault on college campuses and the shameful ways in which the institutions try to cover it up, as when Amherst blamed one survivor and told her to forgive her assailant. This world has long way to go.