> It's that industrialized agriculture had been developed, and thus you could still feed millions of people who were fighting. That sounds like a factor in det

> It's that industrialized agriculture had been developed, and thus you could still feed millions of people who were fighting. That sounds like a factor in determining how long an attacker can sustain attacks, but the underlying hypothesis is that defense far outweighed the ability to sustain attacks. To quote the OP: > "But the real problem was that, for the first time since castles vs. troops without cannon, defense was stronger than offense."