The assassination of President John F. Kennedy on Nov. 22, 1963 still haunts our collective imagination, and rightly so. It was the moment when the entire nation was forced to confront the violence endemic to American life, when people sitting in their own homes watched murder happen. Stephen King's novel 11/22/63 was one of the popular books of 2011. Twenty-five years after nomination for the National Book Award, Don DeLillo's Libra still provokes reflection. References both serious and comic to the murder abound in popular culture. One of the most talked-about episodes of Mad Men tried to recapture the horrified bewilderment of Nov. 22 and its aftermath. The assassination crops up everywhere, from lyrics by They Might Be Giants ("I remember the book depository where they crowned the king of Cuba") to The Seinfeld episode "The Boyfriend," to The X-Files' "Musings of a Cigarette-Smoking Man." There are myriad retellings, explorations and evocations of that day. I recommend the books Six Seconds in Dallas, Case Closed, Mrs. Paine's Garage and the Murder of John F. Kennedy and the American Experience documentary Oswald's Ghost. People are still trying to make sense of what happened on Nov. 22, 1963. One way they do that is to believe in conspiracy theories: It was the CIA, or Castro, or LBJ. Author Fred Kaplan explains why all of those theories are nonsense. Two years ago, Errol Morris presented the solution to one of the most persistent mysteries surrounding the grassy knoll, who was umbrella man? The John F. Kennedy Library and Museum will hold a tribute to JFK this afternoon. Details are here. If you're more interested in Kennedy's life and career than in how it ended, take advantage of the library's pass to the museum and visit in the near future.