Valentine could persuade other people to her point of view—she could convince them that they wanted what she wanted them to want. Peter, on the other hand, could only make them fear what he wanted them to fear.
Note: key character insight
No army had ever fragmented itself like that before, but Ender was not planning to do anything that had been done before, either. Most armies practiced mass maneuvers, preformed strategies. Ender had none. Instead he trained his toon leaders to use their small units effectively in achieving limited goals.
Note: agile teams
“So the whole war is because we can’t talk to each other.”
Note: Those who don't study history are doomed to repeat it.
But somebody with that much compassion could never be the killer we needed. Could never go into battle willing to win at all costs. If you knew, you couldn’t do it. If you were the kind of person who would do it even if you knew, you could never have understood the buggers well enough.”
Note: Ender as the ideal military leader: intelligent, empathetic, & unaware of the enemy's pain.