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In November of 1960, John Fitzgerald Kennedy was elected President of the United States. Three years later, he was assassinated by Lee Harvey Oswald while in a motorcade going through Dallas, Texas.

Had Richard Paul Pavlick gotten his way, Oswald would have never gotten to pull the trigger. Because Pavlick wanted to kill JFK first.

On December 11, 1960, JFK was the president-elect and Richard Paul Pavlick was a 73-year-old retired postal worker. Both were in Palm Beach, Florida. JFK was there on a vacation of sorts, taking a trip to warmer climates as he prepared to assume the office of the President. Pavlick had followed Kennedy down there with the intention of blowing himself up and taking JFK with him. His plan was simple. He lined his car with dynamite — “enough to blow up a small mountain” per CNN – and outfitted it with a detonation switch. Then, he parked outside the Kennedy’s Palm Beach compound and waited for Kennedy to leave his house to go to Sunday Mass. Pavlick’s aim was to ram his car into JFK’s limo as the President-to-be left his home, killing them both.

But JFK did not leave his house alone that morning. He made his way to his limousine with his wife, Jacqueline, and children, Caroline and John, Jr. who was less than a month old. While Pavlick was willing to kill John F. Kennedy, he did not want to kill Kennedy’s family, so he resigned himself to trying again another day. He would not get a second chance at murderous infamy. On December 15, he was arrested by a Palm Beach police officer working off a tip from the Secret Service.

Pavlick’s undoing was the result of deranged postcards he sent to Thomas Murphy, then the postmaster of Pavlick’s hometown of Belmont, New Hampshire. Murphy was put off by the strange tone of the postcards, and his curiosity led him to do what postmasters do — look at the postmarks. He noticed a pattern: Pavlick happened to be in the same general area as JFK, dotting the landscape as Kennedy travelled. Murphy called the local police department who, in turn, called the Secret Service, and from there, Pavlick’s plan unraveled.

The would-be assassin was committed to a mental institution, pending charges, on January 27, 1961, a week after Kennedy was inaugurated as the 35th President of the United States. These charges were eventually dropped as it became increasingly clear that Pavlick acted out of an inability to distinguish between right and wrong (i.e. he was legally insane), but nevertheless, Pavlick remained institutionalized until December 13, 1966, nearly six years after being apprehended, and three years after Oswald pulled the trigger.

Bonus fact: If Pavlick seems old for a would-be Presidential assassin, your instincts are correct. Lee Harvey Oswald was just 24 years old, making him the youngest of all four of the men who assassinated Presidents. John Wilkes Booth was 26 when he killed Abraham Lincoln; Leon Czolgosz was 28 when he assassinated William McKinley, and Charles Guiteau was 39 when he attacked James A. Garfield.