Well, much like those 1960s/70s “bra burnings” that never actually happened…
“The Scottish apparently originated cross-burning, but it was your friends in the mass media who helped sell the idea to the KKK — media being somewhat broadly construed here to include novelists and filmmakers. You think media complicity in the more disreputable aspects of pop culture is a recent phenomenon? Uh-uh. Try 1810.
“The original Ku Klux Klan, which was founded in 1866 and disbanded in the early 1870s, didn’t burn crosses, but that didn’t stop author Thomas Dixon from saying they did in his pro-KKK novel The Clansman (1905). (…)
“Though it had done well enough on its own, The Clansman didn’t become a national phenomenon until Dixon sold the movie rights to the pioneer filmmaker D.W. Griffith, who used it to make his groundbreaking film The Birth of a Nation. In a dramatic scene, the movie’s hero rears up his horse and brandishes a flaming cross to summon the Klans to drive out the black oppressors (!) and their northern white allies who controlled the south during Reconstruction. (…)
“Knowing a good idea when he saw one, William J. Simmons, the founder of the Klan in its second incarnation (1915-1944), cobbled together a cross and burned it at a meeting of the newly-established Knights of the Ku Klux Klan on Thanksgiving night, 1915, on Stone Mountain near Atlanta. Flaming crosses have been a Klan trademark ever since.”
More abortion clinics have been bombed on Law & Order than in real life.