Also, it’s been posted here before, JFK should have been tighter on security, they cancelled a trip to Chicago that year as well. I know there’s a lot to all of this.
I’ve posted the pic before, here’s a link: http://archive2.jfklibrary.org/JFKWHP/1963/Month%2005/Day%2018/JFKWHP-1963-05-18-B/JFKWHP-ST-278-3-63.jpg
You could have almost taken out JFK in Nashville with a knife, he’s so wide-open. I’ve researched this a bit, Ike and Truman probably rode in motorcades, JFK sometimes had tight security, rode in a covered limousine and would stand up out of a hole (like sun-roof) in the roof of the car. Really should have had more caution.
I read the book "Top Down" by Jim Lehrer where it discusses the story behind why they didn't have the bulletproof bubble top on JFKs limo.
The secret service would NEVER let a POTUS ride around in the open like that today.
Even if the POTUS requested it, I'd wager they'd over-rule him.