Citizens, it turns out, are history’s deadliest killers.

From Carnage and Culture by Victor Davis Hanson. Page 131.

The significance of Cannae? The worst single-day defeat in the history of any Western military force altered not at all the final course of the war. Sheer stupidity in the form of incompetent generals and bad tactics had thrown away the intrinsic advantage of Western armies: superior discipline, excellence in and preference for shock engagement, technology, and the readiness to turn out en masse for decisive battle. Poor planning had also nullified the natural advantages that accrued to the embattled Romans: fighting at home, in greater numbers, and on the defensive. Bad luck (fighting a military genius in his prime) and inexperienced soldiers (fresh recruits pitted against a veteran mercenary army) had guaranteed the Romans untold problems. In the end, all that made little difference at all.

The real lessons of Cannae are not the arts of encirclement or Hannibal’s secret of tactical genius, and so they have for too long been ignored by military historians. Students of war must never be content to learn merely how men fight a battle, but must always ask why soldiers fight as they do, and what ultimately their battle is for. The tragic paradox of warfare is that so often courage, audacity, and heroism on the battlefield—what brave warriors can do, see, hear, and feel in the heat of killing—are overshadowed by elements far larger, abstract, and often insidious. Technology, capital, the nature of government, how men are mustered and paid, not merely muscular strength and the multitude of flesh, are the great levelers in conflicts between disparate cultures, and so far more often determine which side wins and which loses—and which men are to die and which to live on.

Naïve Hannibal—who led thousands of tough warriors into Italy in the belief that his genius was to be matched against other generals and warriors similar to his own, rather than pitted against the faceless and anonymous institutions of republicanism and civic militarism itself. Naïve Hannibal—who believed that this war could be decided by his men’s ephemeral heroism and cunning at Cannae rather than by the lasting power of an idea. Citizens, it turns out, are history’s deadliest killers.