Babylon's Ashes by James S. A. Corey
The keel-mounted rail gun pushed the whole ship backward in a solid mathematical relationship to the mass of the two-kilo tungsten round moving at a measurable fraction of c. Newton’s third law expressed as violence.
She wanted to win, to protect her tribe and wipe the enemy into a paste of blood and dismay. But failing that, she wanted to die trying. A snippet of something she’d once read popped in her head: Facing fearful odds protecting the bones of her fathers and the temples of her gods.
The display between them glowed blue and gold. Holden looked tired, but Amos had seen him looking worse one time and another. Holden was the kind of guy who smoked himself down to the filter if he thought it was the right thing to do.
She’d learned more about how to be with traumatized people in the last year than she’d ever hoped to know, and much of what she came to understand was that humans were domestic animals like dogs and cats. They responded poorly to threats and well to a gentle building of trust.