F. Scott Fitzgerald’s Dick Diver, a self-appointed historian, captured the great changes in warfare before 1914. A “beautiful lovely safe world blew itself up with a great gust of high explosive love,” Diver tells a party of American tourists, who were poking around the old trenches on the Somme. By “love,” he meant the obsessive, competitive way in which the great powers had built vast armies, fleets, infrastructure, and arsenals that ensured their mutual destruction in a conflict that Friedrich Engels had predicted (in 1887) would “telescope all of the devastation of the Thirty Years War into three or four years” and gnaw Europe bare “in a way that a swarm of locusts never could.” Aware of the awful risks, European militaries plunged ahead in a general lust for armaments and military organization.

Napoleon Bonaparte had launched warfare into the modern age, and Helmuth von Moltke drove it into the industrial age. Napoleon and his revolutionary colleagues had discovered the merits of general staff work, march tables, army divisions, ordre mixte (alternating shock and fire tactics), and mobile field artillery. Every major army had adopted those Napoleonic “lessons” by the mid nineteenth century, and most assumed that, in so doing, they had done enough. Moltke was not so complacent. Named chief of the Prussian general staff in 1857, he gaped at Prussia’s vulnerabilities. Prussia was a flat, sandy kingdom with growing industries, and surprising quantities of coal, but no natural frontiers. The Rhineland territories that Prussia had acquired in 1815 bordered France but were divided from Brandenburg-Prussia by hostile or unhelpful states like Hanover and Hesse. The Austrian Empire overshadowed (and coveted) Prussian Silesia. Russia flanked Prussia’s eastern heartland from its outposts in Poland and the Baltic. Whereas some of Moltke’s colleagues recommended a pacific foreign policy and continued subordination to Austria and Russia, Moltke, supported by Prussian Minister-President Otto von Bismarck, carried out a military-technological revolution designed not only to solidify Prussia’s defenses, but also to give Prussia the weapons to beat any great power in Europe.