Definition: This term has become more and more used in the world of comic books. A retcon is when a later writer changes the history of a comic book to accommodate their own storyline. The more comic books continue, especially in the case of Marvel and DC, the more history current writers have to wade through. Many feel that it is easier to change the continuity than to have to deal with it.Listening to the Chris Mooney Point of Inquiry interview of Rick Perlstein about leading Republican figures inventing their own versions of history, I could think of no better way to describe their cartoonish historical revisions than as comic book style retcons.
For example, it is easier to change the continuity to accommodate one's own storyline than to have to deal with it. Instead of coming to terms with the overwhelming consilience of evidence for evolution, David Barton simply cites the authority of the Founding Fathers and claims, contrary to reality, that Thomas Paine said that creation science (something that did not exist at the time) should be taught in the classroom instead of evolution (a theory that would not be presented for nearly another 70 to 80 years). Easier, but intellectually corrupt.
The sad part - that Perlstein addresses in the interview - is that media outlets, out of a false sense of balance, now tend to treat such claims as having merit by virtue of their being presented rather than treating them as the obvious nonsense they are.