I have in my hands some American scripture, a small paperback first published in 1969. The book is Thirteen Days, Robert Kennedy's posthumous memoir of the Cuban missile crisis, the moment - 50 years ago last October - we skipped to the edge of nuclear holocaust.
Alongside A Thousand Days - a hagiography of the dead president by White House historian and chief myth-maker Arthur Schlesinger - Thirteen Days quickly became the load bearer for the legend of JFK and the missile crisis. The legend is as smooth as it is enduring: with a cool, calm and compassionate guile, President Kennedy faced down the Soviets and averted Armageddon.
Recently, The Atlantic magazine muscularly dismantled the myth. "Everything you think you know about those 13 days is wrong," ran its lead. Journalist Seymour Hersh did much the same in his 1999 book on JFK, The Dark Side of Camelot. Working from public records, Hersh replaced the wisdom and emotional restraint of myth with JFK's recklessness, bravado and cynical eye to re-election. Claims of Soviet provocation were balanced by repeated attempts to assassinate Castro, the placement of missiles in Turkey and overplaying the Soviet advantage of missiles in Cuba.
In the aftermath of the crisis, JFK publicly presented with deference and humility, the cool grace of a statesman. In private, Kennedy was all swagger and braggadocio, telling friends he'd cut the Soviet leader's balls off.
History is rich with myths and cons - as it is rich with gullibility. For every demented legend, there is a loyal band of acolytes.
Years ago, when I was tutoring high-school English, I helped a student examine another ballad of American scripture - Lance Armstrong's memoir It's Not About the Bike. Retrospectively repugnant, Armstrong's book contained ghost-written treacle such as: ''When I was sick I saw more beauty and triumph and truth in a single day than I ever did in a bike race.'' Amen.
Ostensibly for Armstrong, it wasn't about the bike, and nor was our celebration of his story - a neat and marketable tale of will defeating adversity. The legend is now shattered by more than steroids and blood transfusions.
The US Anti-Doping Agency's report on Armstrong reveals not so much a cheat as a mobster and creep, while the Oprah Winfrey interview revealed a numbingly cold and uninteresting man, his inner life scorched shrubs on flatland.
Last year, the late BBC personality Jimmy Savile - a weirdly iconic man - was revealed to be a serial pederast, aided by a network of rapists. Some years before that, Tiger Woods was undone by sexual indiscretions of a much different nature, but our credulity and the cult of celebrity was similarly revealed.
Woods had been valorised as a paragon of American virtue - yes, the language was that strong - a man who, like Armstrong, had consolidated natural talent with unerring focus and hard work.
None of this is new or interesting in or of itself. As long as we spin around the sun, our little rock will be populated with crooks and hucksters. But what is interesting is our gullibility. What is interesting is how and why we permit wobbly myths and ulterior lives to flourish.
The myths of the Cuban missile crisis were easily sown at the time, given that the documents were classified and the Kennedys had some gifted writers to fill the holes left by redaction. The public grief and amnesia that resulted from Oswald's bullet did the rest.
That was then, but the long-distance stamina of the Kennedy myth has been enhanced by vanity and the rigidity of ideology. It is enormously flattering to believe that American virtue averted end days in 1962, as it is enormously difficult for those raised with the belief that the murdered brothers were unimpeachable exemplars of liberalism to reconsider fact.
Another aid to myth - relevant to Kennedy and Woods - is a reluctance to join private and public morality. Many believe as a matter of faith that the sexual behaviours of public figures should be permanently separated from their public functioning. Sometimes the conflation of the two is the result of puritanism, sometimes of mendacity.
But sometimes the two coincide substantively. JFK's rampant womanising was one clue to his spectacular recklessness, as when he cavorted with the mistress of a mobster. In Woods' case, it wouldn't have mattered publicly, but for his nauseating - and profitable - play-acting as a man of ''family values''.
Public and private morality make a Venn diagram - two independent circles that, at important points, overlap. Ignore this, and you ignore signs of greater public damage.
There's another ingredient of our gullibility - so well demonstrated by Armstrong - and that's our deep familiarity with the language of pop psychology. Our cultural lexicon is full of ''closure'' and ''process'' and ''journey'' and other dead words. In Armstrong's interview with Winfrey, he was simply giving back to her all the silly bromides of self-discovery that she has done so much to popularise. For a man that appears to feel and think so little, a rote learning of this modern vocabulary was enough to counterfeit contrition. His trespasses are too great for it to work now, but flick through his best-selling memoir and the pages are soiled with this glibness. We lapped it up and gave it to our kids.
One last thing. Surveying this wreckage of American credulity, and the pimps that have exploited it, it's hard to find the introverts. But one thing's for sure: they don't often become global brands. Amen to that.
Martin McKenzie-Murray is an Age columnist.