Reading "Masters and Commanders," Andrew Roberts's magnificent account of British and American leaders in World War II, I was struck by how many of them, working prodigious hours and under great strain, were struck down by heart attacks while in their 60s. This doesn't happen anymore, I thought, with the blood pressure and cholesterol medicines many of us routinely take. But it does, as we were reminded by the sudden death at age 69 this week of Richard Holbrooke, who was working prodigiously as Barack Obama's special representative for AfPak, i.e., Afghanistan and Pakistan. Holbrooke was known in cynical Washington...