“You’ve heard the expression “total war”; it’s pretty common throughout human history. Every generation or so, some gasbag likes to spout about how his people have declared “total war” against an enemy, meaning that every man, woman, and child within his nation was committing every second of their lives to victory. That is bullshit on two basic levels. First of all, no country or group is ever 100 percent committed to war; it’s just not physically possible. You can have a high percentage, so many people working so hard for so long, but all of the people, all of the time? What about the malingerers, or the conscientious objectors? What about the sick, the injured, the very old, the very young? What about when you’re sleeping, eating, taking a shower, or taking a dump? Is that a “dump for victory”? That’s the first reason total war is impossible for humans. The second is that all nations have their limits. There might be individuals within that group who are willing to sacrifice their lives; it might even be a relatively high number for the population, but that population as a whole will eventually reach its maximum emotional and physiological breaking point. The Japanese reached theirs with a couple of American atomic bombs. The Vietnamese might have reached theirs if we’d dropped a couple more, 2 but, thank all holy Christ, our will broke before it came to that. That is the nature of human warfare, two sides trying to push the other past its limit of endurance, and no matter how much we like to talk about total war, that limit is always there…unless you’re the living dead.
For the first time in history, we faced an enemy that was actively waging total war. They had no limits of endurance. They would never negotiate, never surrender. They would fight until the very end because, unlike us, every single one of them, every second of every day, was devoted to consuming all life on Earth. That’s the kind of enemy that was waiting for us beyond the Rockies. That’s the kind of war we had to fight.”
―
Max Brooks,
World War Z: An Oral History of the Zombie War