In our adolescence, two friends, my brother, and I spent many summer days playing war in the fields and woods near my house. We fought British Redcoats, Yankees and Rebels, Nazis, and many times, each other. When I was 11 and received a BB gun, we’d fire away for hours at bottles or at targets we’d drawn on cardboard boxes. In 1969, I entered the U.S. Military Academy. That summer as a plebe, using an M-14, I qualified as an expert on the firing range. The next summer, when I was a yearling, which is a sophomore, my classmates and I fired M-16s, grenade launchers, artillery, M-60 machine guns, and tanks. After my resignation in the middle of my yearling year—honorable, by the way—I occasionally would go shooting with friends. When my children were growing up, I took them into the woods and let them plink away first with a …