The president of the United States travels to Texas to mitigate factional strife in his Democratic Party, and on Nov. 22, 1963, is gunned down on a Dallas street. Two days later, alleged assassin Lee Harvey Oswald is shot by hustler Jack Ruby. JFK’s majestic Nov. 25 funeral, planned in detail by wife Jacqueline, provides no closure. American government has been fundamentally shaken. Oswald’s televised murder precludes a trial, and greatly encourages conspiracy theories. Fascination with, and controversy about President Kennedy continues. In 2013, floods of books, articles and commentaries mark the half-century since his death. Kennedy’s legacy is complex...