The world stood at the brink of Armageddon for 13 days in October 1962 when President John F Kennedy drew a symbolic line in the Atlantic and warned of dire consequences if Soviet Premier Nikita Khrushchev dared to cross it.
An American U-2 spy plane flying high over Cuba had snapped aerial photographs of Soviet ballistic missile sites that could launch nuclear warheads with little warning at the US, just 90 miles away. It was the height of the Cold War, and many people feared nuclear war would annihilate human civilisation.
Soviet ships carrying nuclear equipment steamed toward Kennedy's "quarantine" zone around the island, but turned around before reaching the line. "We're eyeball-to-eyeball, and I think the other fellow just blinked," US Secretary of State Dean Rusk famously said, a quote that largely came to be seen as defining the crisis.
In the five decades since the nuclear standoff between Washington and Moscow, much of the long-held conventional wisdom about the missile crisis has been knocked down, including the common belief that Kennedy's bold brinksmanship ruled the day.
On the eve of the 50th anniversary of the Cuban missile crisis, historians now say it was behind-the-scenes compromise rather than a high-stakes game of chicken that resolved the faceoff, that both Washington and Moscow wound up winners and that the crisis lasted far longer than 13 days.
Declassified documents, oral histories and accounts from decision-makers involved in the standoff have turned up new information that scholars say provides lessons for leaders embroiled in contemporary crises such as the one in Syria, where president Bashar Assad has ignored global pleas to stop attacks on civilians.
Another modern standoff is over Iran, which the West accuses of pursuing a nuclear weapons program. In a recent UN speech, Israeli PM Benjamin Netanyahu drew a red line on a cartoon bomb to illustrate that a nuclear Tehran would not be tolerated.
"Take Iran, which I have called a Cuban Missile Crisis in slow motion," said Graham Allison, author of the groundbreaking study of governmental decision-making "Essence of Decision: Explaining the Cuban Missile Crisis."
"This same process is looming on the current trajectory, inexorably, toward a confrontation at which an American president is going to have to choose between attacking Iran to prevent it becoming a nuclear weapons state or acquiescing and then confronting a nuclear weapons state," Allison said.