The problem, esp. in the U.S., is neither biased history, nor cosmetically-altered history, but forgotten history (or history that was never remembered to begin with). Gore Vidal wrote his American Chronicle series of novels to combat not only the common, prettified history, but also the general “United States of Amnesia” that encourages and coerces (through compulsory schooling) forgetting. My experience teaching history in the middle grades (6–9) convinced me that the subject is deliberately neglected, underfunded, and backwards, because nobody knows how to use it in education, and the directors of schools secretly wish they didn’t have to teach it, and that it would just go away. The “iconoclasts” that deface the statues and remove the markers (!) are just advancing the ruling class’s schooled amnesia, so that they can continue to be, as Vidal once noted, invisible (to the ignorant).
