The speculation immediately after the assassination may have pointede in the direction of three assassins, but the speculation on 9/11 was that the State Department had been blown up. News last night was that 12 men trapped in a mine had survived. News during an event or in the immediate aftermath is rarely reliable.
Oswald was the only lone-nut assassin in US history who did not proudly claim his crime. He called himself a patsy. And of course, the proof of conspiracy (at least for me) was Jack Ruby, a long-time minor mob figure showing up at just the right moment in Oswald's transfer to kill him.
I still think it was a setup. And I still bet it was LBJ and Hoover.