America knew him as a toddler laughing on his father's knee, in the days when Secret Service agents taught him to box. We wept for him on the day he turned three, as he saluted his slain father. Between that day and last Friday night, when he died in a plane crash with his wife, Carolyn, and sister-in-law Lauren Bessette, John F. Kennedy Jr. spent 3� decades as a sportsman. A lifelong baseball fan (above, with Willie Mays at Shea Stadium in 1972), he spent last Thursday night at Yankee Stadium watching the Braves beat Roger Clemens. The founder and editor of George magazine was an outdoorsman who skied, hiked, biked, sailed, rafted, snorkeled and skin-dived. He played tennis and of course touch football and was often spotted in New York throwing Frisbees in Central Park or rollerblading on Madison Avenue. Death devoted far too much attention to him and his family, but still he ran, swam and bladed hundreds of miles, broke countless honest sweats and never seemed less than fully alive.