My initial plunge into leadership came during World War II. I was a lieutenant in the infantry, 19 years old, and scared out of my wits. My orders were to assume command of a platoon on the front lines in Belgium. I arrived in the middle of the night, when most of the men were asleep. The platoon had taken up residence in a bombed-out shell of a house. I was led into the kitchen by the platoon’s runner, and he offered me a bench to sleep on. Instead, I put my sleeping bag on the floor, next to the rest of the men. Not that I slept. I lay awake all night, listening to the bombs explode. I was as green as can be and knew little about command—or the world, for that matter. When the others in the house began to stir, I heard one sergeant ask another, “Who’s that?” “That’s our new platoon leader,” the man answered. And the sergeant said, “Good. We can use him.”

A version of this article appeared in the January 2004 issue of Harvard Business Review.