President John F. Kennedy in the Oval Office of the White House in Washington, Feb. 19, 1961. Though the Cuban Missile Crisis took place over a year later, the image has become an iconic representation of what has been characterized as the loneliest job in the world. This October, 2012, marks the 50th anniversary of the confrontation between the U.S. and the Soviet Union over their positioning of nuclear missiles in Cuba. (George Tames/The New York Times)