Is Donald Trump a self-made business genius, or a tycoon's son who was “born on third base and thinks he hit a home run”?

Did Ted Cruz’s father really fight for Fidel Castro – and did Marco Rubio’s parents really flee Cuba to get away from Castro?

Did Carly Fiorina effectively lead tech giant Hewlett Packard, or nearly destroy it? Did Ben Carson embellish his autobiography? Did Hillary Clinton try to join both the Marines and NASA?

Decades before the 2016 presidential candidates struggled to tell their biographical narratives, a U.S. Senator rode one moment from his “creation story” all the way to the Oval Office, where he became America’s most popular modern president. He did it by exploiting a World War II incident that killed two of his own men and led some of his colleagues to privately accuse him of negligence.

On August 2, 1943, during a chaotic skirmish amid the Solomon Islands, the Japanese destroyer Amagiri struck the U.S. Navy's PT 109 boat skippered by Lt. (jg) John F. Kennedy, destroying the craft and killing two American sailors instantly. The starving survivors were rescued a week later and Kennedy was awarded a lifesaving medal for saving one of his own men and holding the rest together during the ordeal.

Months later, on June 17, 1944, an article on PT 109, written with JFK’s cooperation and editorial approval, appeared in The New Yorker magazine, later condensed in the mass-market Readers Digest. It portrayed Kennedy as a mythic action-hero. For John Kennedy’s father, financial mogul Joseph P. Kennedy Sr., the article was a perfect instrument to thrust his son into the national spotlight.

The Kennedys blanketed key election districts with reprints of the article in JFK’s election to Congress in 1946, the Senate in 1952, and the presidential election of 1960. The PT 109 story worked every time, and became the ultimate campaign weapon.

Over the years, some critics accused Kennedy of negligence in the PT 109 incident, focusing on Kennedy’s decision to hold at his boat’s position in the water with two of its three engines disengaged, which reduced his reaction time. But this was an understandable improvisation since it reduced the boat’s telltale “wake” of bubbles that could act as a target beacon for Japanese aircraft, and it allowed Kennedy’s crew to hear the approach of such planes better in the blacked-out, moonless night.

The bigger question was why, having received a clear radio warning of Japanese destroyers in the area (a critical admission JFK makes in the an extremely rare first-hand account of the incident he compiled in 1946, uncovered in the files of the John F. Kennedy Presidential Library and published in full for the first time in my book, "PT 109: An American Epic of War, Survival, and the Destiny of John F. Kennedy"), Kennedy allowed four of the twelve men under his command, fully one-third of his crew, to be asleep or reclining on deck when the Japanese destroyer approached, rather than alert and on the lookout, in which case they might have spotted the fast-moving enemy ship a few crucial seconds earlier.

The explanation may lie in Kennedy’s reputation for being a very kind leader to his crew. His men were exhausted from weeks of round-the clock patrols, and he may have guessed he could get away with giving them a break. It proved to be a fatal, and history-shaping, mistake.

The PT 109 incident made John F. Kennedy—both the man and the myth. Without Kennedy, the contours of modern American history that he helped shape during his brief but consequential presidency might have turned out quite differently.

Presidential campaigns have always exploited their candidates’ biographical narratives, sometimes exaggerating them in the process, as critics claim is being done today by several 2016 White House hopefuls.

Today, as in the age of JFK, “the story” is everything in Presidential campaign politics. It is the narrative of personal struggle, courage and achievement that defines a candidate, and it is largely what the electorate votes for.

Pundits swoon for candidates with “a good story” like Ted Cruz and Marco Rubio, both Cuban immigrant sons who embody the American dream. Ben Carson’s story often boils down to that of a neurosurgeon grappling with the cosmic issues of life and death inside the operating room. Donald Trump’s story is that of a lifetime of bombastic media performance art, Hillary Clinton’s that of liberal crusader and globetrotting Secretary of State, and Jeb Bush’s that of an effective Florida governor.

But in the hands of Joseph and John Kennedy, the PT 109 saga, depicting JFK as a daring war hero facing the ultimate test of courage and survival in the combat zone, became the mother of all modern presidential creation stories.

As longtime JFK aide David Powers put it, “Without PT 109, there never would have been a President John F. Kennedy.”