“Recent scholarship confirms the portrait of John F. Kennedy sketched by his brother in Thirteen Days: a remarkably cool, thoughtful, nonhysterical, self-possessed leader, aware of the weight of decision, incisive in his questions, firm in his judgment, always in charge, steering his advisers perseveringly in the direction he wanted to go. “We are only now coming to understand the role he played in it,” writes John Lewis Gaddis, the premier historian of the Cold War.”