For 13 days in October 1962, President John F. Kennedy faced the task of avoiding Armageddon. American reconnaissance planes had just detected Soviet missiles in San Cristóbal, a city in western Cuba, and the United States was determined to expel them. The Soviets and Cubans were equally determined to keep those weapons in place.
In deciding what to do, Kennedy found himself facing off against his own Joint Chiefs of Staff, who unanimously recommended a full-scale attack and invasion of Cuba, as did other top advisers. Kennedy feared that such an attack would lead to the Soviet Union using nuclear weapons against the United States, to which America would have to respond in kind. Millions, perhaps billions, would be killed.

Comments
Interesting viewpoint of Tuchman's book. I read it and was left with the definate impression that both Germany and France prepared for the "Next War" starting from the Franco-Prussian war of 1870. Nothing was accidental when it finally broke out. Perhaps JFK saw the same and realized the Cold War would push us to another World War, but with nuclear weapons, if we let it.
Isn't it also possible that JFK used the book as way to send a message of the path he wished to take? Perhaps he valued the message of "war is not inevitable but it is the result of leadership" secondary to the historic specifics as understood at the time. His leadership was towards peace no matter the tool.