"We never had any hope of saving his life." (A doctor in the emergency room)

In the 19th century, the Scottish writer Thomas Carlyle famously wrote, "The history of the world is but the biography of great men," popularizing the "Great Man" theory that the course of history is shaped by a select few heroic individuals. While historians and others continue to debate the accuracy of the Great Man theory of history, there is no question that the course of history is permanently altered by decisive moments in time, where a different result would have produced drastically different outcomes. Charles River Editors' Decisive Moments in History examines the events that changed history forever and set the world down the path it finds itself on today.

In the annals of American history, only a few moments have been so thoroughly seared into the nation's conscience that Americans can remember exactly where and when they heard about an earth-shattering event. In the 20th century, there was Pearl Harbor and the assassination of President John F. Kennedy.

November 22, 1963, started as a typical Friday, and many Americans were unaware that President Kennedy was even heading to Dallas, Texas. John and Jackie arrived in Dallas in the morning, with Texas Governor John Connally alongside them and Vice President Lyndon B. Johnson due to arrive later to meet them there. The Kennedys and the Connallys intended to participate in public events later in the day, and Jackie and John were pleasantly surprised by the warm reception they received....