I firmly believe that the mob had JFK killed.....I am sorry but Jack Ruby was no patriot and I believe he hated Kennedy. No reason to shoot Oswald unless he was sent there to silence him.
I believe the mob used Oswald to do it. The shots were outstanding, but not impossible, and many believe not even exceedingly difficult. I mean it reeks of Marcello, Traficante, and Hoffa....use limited number of people and then kill the shooter using someone you know won't crack. Ruby was a mobster wannabe and this was his way of become a made man.
While the mob loves to bolster itself, I don't believe they would take the heat for this one unless they really did it. It is the simplest theory.....JFK gets elected with the mob's influence, he almost immediately starts going after the mob after the failed bay of pigs mission, and they killed him.
http://www.spartacus.schoolnet.co.uk/JFKmarcello.htm
"On 14th January, 1992, the New York Post claimed that Marcello, Jimmy Hoffa and Santos Trafficante had all been involved in the assassination of President John F. Kennedy. Frank Ragano was quoted as saying that at the beginning of 1963 Hoffa had told him to take a message to Trafficante and Marcello concerning a plan to kill Kennedy. When the meeting took place at the Royal Orleans Hotel, Ragano told the men: "You won't believe what Hoffa wants me to tell you. Jimmy wants you to kill the president." He reported that both men gave the impression that they intended to carry out this order.
In his autobiography, Mob Lawyer (1994) (co-written with journalist Selwyn Raab) Frank Ragano added that in July, 1963, he was once again sent to New Orleans by Jimmy Hoffa to meet Marcello and Santos Trafficante concerning plans to kill President John F. Kennedy. When Kennedy was killed Hoffa apparently said to Ragano: "I told you could do it. I'll never forget what Carlos and Santos did for me." He added: "This means Bobby is out as Attorney General". Marcello later told Ragano: "When you see Jimmy (Hoffa), you tell him he owes me and he owes me big."
Cal