Allan Lichtman’s forecast model was meant to be foolproof. He explains to David Smith what was different this time

Surely not even Nostradamus could get it right all of the time.

Allan Lichtman had correctly forecast the result of nine of the past 10 US presidential elections (and even the one he didn’t, in 2000, he insists was stolen from Al Gore). His predictive model of “13 keys” to the White House was emulated around the world and seemed all but indestructible.