The most profound question is, "What would I risk dying for?" The natural answer is "for my family." But for most of history, we didn't live in families. We lived in small communities that gave us our sense of safety and place in the world, so the natural answer would be "for my people." The blessing and the tragedy of modern life is that we don't need our community to survive anymore. When we lose that idea, we lose a sense of who we are.

There's no reason to do anything twice, and certainly no reason to do something that almost killed you.

Combat isn't where you might die -- though that does happen -- it's where you find out whether you get to keep on living. Don't underestimate the power of that revelation. Don't underestimate the things young men will wager in order to play that game one more time.

Often people who live through the trauma are nostalgic when it's over. When I went back to Bosnia 20 years after the brutal civil war, even people who had been badly wounded told me they missed those times. They were missing their more courageous selves.

I was surprised how open and unguarded the military was. I expected more scrutiny, more supervision from command.

I went to Afghanistan in '96 to write about terrorist training camps south of Jalalabad and Tora Bora, in the mountains. I was there right before the Taliban took over, literally a few weeks before they took Kabul. The frontline wasn't terribly active, but it was definitely there. And they swept into power.

Of the primary emotions, fear is the one that bears most directly on survival. Children show fear. Adults try not to, maybe because it's shameful, or, in some circumstances, dangerous. The fear response is automatic, though, and your body runs through its reflexes whether you want it to or not.