Nearly 50 years after the Cuban missile crisis, the danger of a nuclear attack on the U.S. is compounded by a false sense of safety and the widely accepted notion that eradicating nukes is a pipe dream. This documentary from producer Lawrence Bender (An Inconvenient Truth) attempts to shake up the equation, portraying a future attack as probable yet making the gradual elimination of weapons-grade material seem achievable. The movie takes as its mantra and organizing principle President Kennedy's observation, during his 1961 speech to the United Nations, that "every man, woman, and child lives under a nuclear sword of Damocles, hanging by the slenderest of threads, capable of being cut at any moment by accident, or miscalculation, or by madness." Surveying the past few decades, the movie supplies numerous examples of the first two, while the prospect of Al Qaeda acquiring a nuclear device takes care of the third. Lucy Walker directed.