Military staffs need historical judgment alongside enthusiasm

Should military units above a certain level include a historian on their staffs?

Official historians are not usual in this account, but amateur historians are common and occasionally include someone with substantial knowledge.

Official staff historians are contrasted with the amateur historians commonly found on military staffs. In Clarke's experience, several people on a staff will regard themselves as knowledgeable about history. He distinguishes that confidence from the rarer case of someone who has the knowledge to justify it.