It's fifty years ago today since you-know-what, and although generally I'm slow to assume a conspiracy (I'm still awaiting a credible and reasonably coherent MIHOP theory for 9/11 for example) I do join the 61%  who still think Oswald didn't act alone.
The mainstream media (MSM) have been busy this month trying to convince this 61% to change our minds, and that makes me wonder: why bother?
Suppose arguendo that they are right; that Lee Oswald was a low-life with big ideas and small talent, who wanted to gain immortality by doing an historic thing. Jacob Hornberger has an interesting take on that, by the way, here on FFF . If it were so, the killing would be a tragedy like all deaths, but not much more. Why the fuss? - methinks the MSM doth protest too much.
Cui bono? - a long list; LBJ gained the Presidency, and by re-activating the Vietnam war he gained a fortune from his holdings in military contractor firms. The whole Military Industrial Complex likewise gained huge business. The CIA was pulled back from the very brink of JFK-planned extinction. The Mafia gained vengeance on the power behind RFK, who had double crossed it by waging war on it after it had favored his brother by getting out the graveyard vote in Cook County as a favor to their old bootlegger buddy Joseph, the brothers' pa.
And who were best placed to choreograph the assassination? - the very same list.
Now, if the great American public formed a fixed opinion that a President, his intelligence staff, his friends in industry, and some of the most distinguished godfathers in American crime had all systematically conspired to commit murder, frame a patsy, and fool us all for half a century, the tatters of confidence in the established order would be swept away.
So, they worry :-)