As he unpicks the fantastical beliefs that run through America's past and present, the writer and broadcaster Kurt Andersen asks if the US is now entering a post-truth era.

The author of Fantasyland and co-founder of Spy magazine, Kurt has spent many decades separating fact and fiction and in this essay he explores the historical roots of America's weakness for alternative realities.

From the religious visions of the Pilgrim Fathers and Joseph Smith, to the showbiz dreams of PT Barnum and Walt Disney, the proliferation of conspiracy theories and the new age of virtual reality and internet chat rooms, Kurt tells the story of a nation in which fantasy and reality have long been intertwined.

Producer: Julia Johnson. Show less