Early in the novelization of the story, Shel has a conversation with his dad about the chronological integrity principle. There is only one timestream, and if we try to do anything to change what is already known about the stream, then time will stop us. On the other hand, if we can arrange for an event to happen that meets the known facts without being quite what we thought it was. . .
What did you try to do? Post somebody at the Texas School Book Depository?

Variants

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  1. Time Travelers Never Die by Jack McDevitt (Ace Books, November 2009).
    2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Jack McDevitt