Fighting in the Napoleonic Wars was in the continuity of the eighteenth century and even the two preceding ones. Major changes in weapons on a large scale would not occur before the years 1850. Generals and officers were still nurtured by the military writers of the eighteenth century, but among these writers some had envisioned what war could become if large-scale ‘operations’ were conducted and if armies grew in size. With the Revolution and the dictatorial power Napoleon inherited from it, France set the tone for waging war with more intensity, in the movement of armies as well as in tactics on the field of battle. Other powers simply had to follow, but interior conditions and social imperatives resulted in partly adaptations and half-measures.

Chapter 2 surveys and analyzes the greatest ideas and theorists in war theory and strategy – including the philosophies of Sun Tzu, Thucydides, Machiavelli, Jomini, Clausewitz, Liddell Hart, and Mao. This chapter makes war theory and its recurring themes more accessible by presenting diverse perspectives spanning all eras of military thought from classical through the twentieth century. Each theorist’s background and main ideas are presented, and their strengths and weaknesses are summarized. As history’s preeminent but also most misunderstood war theorist, special attention is given Clausewitz. Principal themes include war’s fluidity, unpredictability, violence, and reciprocity; concentration and momentum; adaptability, intelligence, and relative capacity; military genius; centers of gravity and decisive points; fog, friction, chance, and policy; guerrilla, asymmetric, and nuclear warfare; and war’s moral and physical dimensions.