As for the soldier dream, i've heard of people who've had ancestors who lived through things like the Holocaust have flashbacks from their ancestor's experiences. I'm a scientific type and I can't think of any explanation, but trauma does, actually, alter/damage the genetic code and affect subsequent generations.
I've had several dreams, starting when I was about 4 or 5, where I'm flying above mountains in a plane with engines so loud they drown out any sound. As I look down, I see the skeletal wrecks of other planes strewn across the snow-covered ground below. The air is so thin that I'm struggling to breathe, and my heart is beating too fast and shallow in my ears.
The real kicker is that my grandfather served in the Army Air during WW2. He flew dozens of missions as part of a cargo squad over the Hump, or the "aluminum trail", a dangerous route through the Himalayas named for the wrecked planes along it. He had had polio as a kid, which had weakened his heart; the Army Air didn't know this the entire time he served. He died of heart failure before I was born, and no one told me about his time in the service until I was about 9. But for years before I knew, I'd been having dreams that seemed like flashes of his memory. I've never been able to figure out how it happened.