He was a third-rate president who gave a few good speeches. Much of this was known at the time, but the media kept it from the public. Yet the same media turned him into our nation's secular saint after his death. Camelot, my arse! Academia has taught subsequent generations of school kids that Kennedy was a great president. To all of which I say, phooey!
One reason the assassination as a crime is so open to all sorts of conspiracy theories is that the line of those who wanted JFK dead was such a long one. Consequently, there are several plausible scenarios as to motive.
However, the Zapruder film showed both at the time, and for all time since, that the fatal shot came from the rear and exploded the upper right front of the president's skull. As I've already pointed out, the difference in behavior between that round and the other two known rounds may be suggestive of two shooters. Perhaps there's a plausible explanation, but I would need a ballististics expert to explain how the same type of ammunition could behave so differently. But as to the direction of the fatal shot, there is absolutely NO DOUBT whatsoever that it came from the rear. None. And I'll repeat: anyone who has seen the Zapruder film in slow motion and still claims the fatal shot came from the front is a charlatan.
Here is an animated gif that show the moment of impact. Kennedy moves to the front after the round impacts his skull -- not "back and to the left" like Oliver Stone convinced so many people. It's is crystal clear that the bullet came from the rear.
Put your cursor on the door handle highlight, on Jackie's hat, or on the back of the seat. They are all still. Now put it on Kennedy's head. It is thrown forwards when the bullet hits.