When President Biden compared Russia's nuclear threat against Ukraine to the 1962 Cuban missile crisis, it highlighted just how much that Cold War showdown continues to shape our collective psyche.

Although Biden's remarks earlier this month about the "prospect of Armageddon" have been labeled alarming by some and alarmist by others, they emphasize that the stakes in any such conflict between nuclear-armed rivals have not changed since the infamous "13 days" of the crisis.

"We came really close to nuclear catastrophe," says Fredrik Logevall, a Harvard history professor and author of JFK: Coming of Age in the American Century, 1917-1956.

The crisis began on the morning of Oct. 16, 1962. President John F. Kennedy was shown photos taken by a U-2 spy plane indicating Soviet ballistic sites under construction on the island of Cuba. Once operational, he was informed, they could be used to launch a nuclear strike on the U.S. mainland virtually without warning.

The first of a series of meetings of top advisers and Cabinet officials was quickly convened, including the president's brother and close confidant, Attorney General Robert F. Kennedy.

When President Biden compared Russia's nuclear threat against Ukraine to the 1962 Cuban missile crisis, it highlighted just how much that Cold War showdown continues to shape our collective psyche.

Although Biden's remarks earlier this month about the "prospect of Armageddon" have been labeled alarming by some and alarmist by others, they emphasize that the stakes in any such conflict between nuclear-armed rivals have not changed since the infamous "13 days" of the crisis.

"We came really close to nuclear catastrophe," says Fredrik Logevall, a Harvard history professor and author of JFK: Coming of Age in the American Century, 1917-1956.

The crisis began on the morning of Oct. 16, 1962. President John F. Kennedy was shown photos taken by a U-2 spy plane indicating Soviet ballistic sites under construction on the island of Cuba. Once operational, he was informed, they could be used to launch a nuclear strike on the U.S. mainland virtually without warning.

The first of a series of meetings of top advisers and Cabinet officials was quickly convened, including the president's brother and close confidant, Attorney General Robert F. Kennedy.

The group ultimately settled on a naval quarantine, or blockade, of Cuba to force Soviet Premier Nikita Khrushchev to remove the missiles. Ultimately, Khrushchev received an assurance that the U.S. would not invade Cuba and, in a deal that remained secret for a quarter century, the U.S. also promised to remove its missiles from Turkey.

In the 60 years since the Cuban missile crisis, new information has come out that sheds light on the events of October 1962. Here are three key things that you may have missed in history class:

Saturday, Oct. 27, 1962, "was not only the most dangerous moment of the Cold War," Arthur M. Schlesinger Jr., a senior Kennedy adviser, has written. "It was the most dangerous moment in human history."