I think that certain emotions can compromise you when you’re at war. If you stop to mourn the dead, or even to breathe in what you’ve done, you’ll be dead as well. Your brain goes to a primitive region, one inaccessible to feelings beyond pure anger and pure fear. Your brain is reduced to two impulses: fight or flight. Kill or be killed. No room for more delicate feelings. No room for a soul. All you’re thinking about is how to maneuver your body in space so it will survive.