Originally conceived to mark the 50th anniversary of the 1909 Alaska–Yukon–Pacific Exposition, the major theme of the fair was to show that the United States was not really behind the Soviet Union. As a result, the major themes were of space, science, and the future.
Although President John F. Kennedy was supposed to attend the closing ceremony of the fair on October 21, 1962, he bowed out, pleading a “heavy cold.” It later became public that he was dealing with the Cuban Missile Crisis.
Source:Wikipedia