Dangerous Games by Margaret MacMillan

"Historians, however, are not scientists, and if they do not make what they are doing intelligible to the public, then others will rush to fill the void. Political and other leaders too often get away with misusing or abusing  history for their own ends because the rest of us do not know enough to challenge them. Already much of the history that the public reads and enjoys is written by amateur historians. Some of it is very good, but much is not. Bad history tells only part of complex stories. It claims knowledge that it could not possibly, have, as when, for example, it purports to give the unspoken thoughts of its characters."