What is the author's tone in The Mask of Command by John Keegan?

The tone used in Mask of Command by John Keegan is objective in nature. Sir John Keegan (1934 - ) is a British military historian, lecturer, writer for the National Review Online, and Defence Correspondent and Defence Editor for the Daily Telegraph. Throughout the years, Keegan has devoted himself to writing about a wide variety of military heroes and battles from an academician's point of view. Keegan also manages to impart information that interests the non-academic reader.