Dictators and democrats seeking to deflect blame for their own incompetence have always manipulated the truth; sore losers have always accused the other lot of lying.
But post-truth politics is more than just an invention of whingeing elites who have been outflanked. The term picks out the heart of what is new: that truth is not falsified, or contested, but of secondary importance. Once, the purpose of political lying was to create a false view of the world. The lies of men like Mr Trump do not work like that. They are not intended to convince the elites, whom their target voters neither trust nor like, but to reinforce prejudices.
Source: Art of the lie | The Economist