Lee Harvey Oswald bought a $19 military surplus rifle out of a magazine and killed him because he was a communist wack job with a political agenda that wanted to be famous.

True, there were a lot of people all over the world that weren't all that sorry JFK was dead for various reasons which is the foundation of all the conspiracy theories. So many people could have had motive.

Most Americans don't want to believe or can't believe that a single simple minded person could get to the POTUS. But that is exactly what happened. There is only fantastic speculation, but not a single shred of evidence to support otherwise, but Americans for the most part can't be bothered or confused by facts if it doesn't serve their purpose or cause.

Widespread election fraud only being committed when Republican candidates loose elections being the most recent example. No Republicans question or contest any elections they win.

Another argument and conclusion of convenience.

"You cannot invade mainland America. There would be a rifle behind every blade of grass"
~Admiral Yamamoto~

When the people fear their government, there is tyranny; when the government fears the people, there is liberty. ~Thomas Jefferson~