Several years after she orchestrated John's funeral, she was filled with fear for herself and her children, John and Caroline. In June 1968, when her brother-in-law Robert F. Kennedy was assassinated, she came to fear for her life and that of her children, saying "If they're killing Kennedys, then my children are targets...I want to get out of this country." On October 20, 1968, she married Greek shipping magnate Aristotle Onassis, who provided her both privacy and security. Jacqueline Onassis and her children moved to Onassis' private Island in the Ionian Sea.
So we question what motivated Oswald to shoot the president? He had ties to Cuba, and to Russia, but politicians often (as in Watergate, e.g.) use dirt-level agents with foreign connections to do their bidding. When caught, the foreign ties tie in with motivation.
Was Ruby a hired assassin, brought in to prevent the man who shot the president from revealing information? Was jealousy a motive, involving an affair between the president and the most famous Marilyn Monroe?
Many have been blamed, but the controversy remains unsolved.