Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Short, succinct, and thought-provoking.

I have always viewed fans of military history with suspicion, having known too many who are weapon-fetishists, power-worshippers or simply ghouls. Fortunately for me, a sane, gentle friend read and recommended this book (thanks Mike Malcolm, where ever you are), introducing me to a now favorite author. MASK analyzes and contrasts the military leadership of four men: Alexander, Wellington, Grant and Hitler. Each profile is fascinating in itself, but what impressed me profoundly was the final chapter, in which Keegan brings everything together, enumerating the "imperatives" of military authority throughout history, and finally asking how those imperatives can be met in the nuclear world, where the civilian population is on the front lines and generals must necessarily "lead" from behind. I recommend this book (and all Keegan's work) wholeheartedly to anyone who would never dream of reading "military history".