Americans have been slow to respond to climate change, and this trenchant advocacy documentary (2007) lays much of the blame on Washington bureaucrats, lobbyists, and TV news programmers, all of whom spent two decades framing the dangers of global warming as debatable despite mounting scientific evidence. Journalists Bill McKibben and Ross Gelbspan and government whistle-blower Rick Piltz describe their Sisyphean battles against vested interests, and their doggedness is heartening; so are the comical but successful efforts of grassroots activist Bish Neuhauser to fuel his car on biodiesel. Daniel B. Gold and Judith Helfand directed, following up their 2002 collaboration Blue Vinyl. 94 min.