JFK's Assassination: Conspiracy or Not?

I do not believe that JFK's assassination was a conspiracy. I feel that if it was planned to be a conspiracy then an escape route for Oswald would have been made available. I also feel that other individuals would of had to be involved in this conspiracy because it is such a huge task to accomplish: assassinating the beloved president. Plus, it is part of human nature to have a guilty conscious. I feel like someone who was involved in the conspiracy might have changed there mind and noticed what an awful thing they were going to do to the nation. I just strongly feel as though the assassination of JFK was not a conspiracy because all of the pieces of the puzzle don't match up, and if it was someone would have been caught by now.