Franklin D. Roosevelt, whose calmness is often recalled in discussing Mr. Obama, may have gotten it from his parents. According to Jonathan Alter’s account in "The Defining Moment," when the family was aboard the ocean liner Germania as it plunged beneath a giant wave, F.D.R.’s father remarked coolly, "We seem to be going down." His mother took her fur and nestled 3-year-old Franklin into it: "Poor little boy, if he must go down, he’s going down warm."