In the fall of 1962, cadets at New York Military Academy were consumed by a terrifying prospect: nuclear apocalypse.

Soviet ships had delivered nuclear weapons to Fidel Castro’s government, which was busy installing them on the island just 90 miles from the United States.

In their barracks at the military academy an hour north of New York City, cadets huddled around radios each night to learn if Armageddon was at hand. On Oct. 22, they listened intently as President John F. Kennedy delivered a stern address on the rapidly spiraling crisis.

“It shall be the policy of this nation to regard any nuclear missile launched from Cuba against any nation in the Western Hemisphere as an attack by the Soviet Union on the United States, requiring a full retaliatory response upon the Soviet Union,” Kennedy warned.

Among the cadets at the academy in that fraught, fear-filled autumn was a 16-year-old junior named Donald J. Trump.

Fifty-five years later, President Trump now finds himself facing a nuclear crisis of his own.

“North Korea best not make any more threats to the United States,” Trump told reporters on Tuesday. “They will be met with fire and fury like the world has never seen.”

Trump’s comments echoed President Truman’s warning to Japan two days after the bombing of Hiroshima that if the country didn’t surrender, it faced “a rain of ruin from the air, the like of which has never been seen on this Earth.”

But as a threat by an American president to another nuclear-armed state, Trump’s warning is without precedent, experts say.

It has set off intense speculation over Trump’s willingness to use America’s nuclear arsenal, as well as questions about his temperament as president.

To Trump’s former classmates, however, his blunt words reflect the influence not only of the military academy they attended but also the Cuban missile crisis they endured together.

“Here we were, we’re basically teenagers, and we are believing that New York is very possibly about to get a hydrogen bomb dropped on it,” recalled Peter Ticktin, a Florida attorney who was in Trump’s 1964 graduating class. “We were basically thinking that this is the end.”

New York Military Academy was founded in 1889 by Civil War veteran Charles Jefferson Wright. It boasts of its record whipping rebellious youths into shape. “Courageous and gallant men have passed through these portals,” reads an inscription over the front door.

On top of such courses as math and English, students tackle military history and learn how to fire rifles and mortars.

Few instructors spoke about the situation with Cuba, even as November approached and the missile crisis deepened, cadets recalled.

But it was all the students could talk about, remembered Ticktin and two other former cadets reached by phone Wednesday.

“We were just listening to every piece on the radio,” said George White, who at the time spelled his last name Witek. As they gathered in their rooms at night, some of the students nervously smoked contraband cigarettes. At one point, White accidentally sat on a smoldering cigarette, ruining his school uniform.

“It was intense,” he said.

Adding to the fear was the expectation that cadets, particularly older students such as Trump, could be called upon in the case of nuclear war.

“We weren’t just kids,” said Ticktin. “We were kids who had M-1 [rifles]. We were kids in uniform.”

“We knew they would use us to keep order,” he added. “If we weren’t all dead.”

“Basically the thought was we were going to war,” said Jack Serafin, a Florida businessman who was a freshman at the time of the Cuban missile crisis.

Tensions inside the barracks — and across America — built over the week after Kennedy’s address until, on Oct. 28, Soviet Union leader Nikita Khrushchev announced on Soviet radio that the country would remove the nuclear weapons from Cuba.

“When the announcement was made that the Russian ships were turning back … it was a sigh of relief,” Ticktin recalled.

Ticktin, who is a Trump supporter and donor, said he saw parallels between Kennedy’s handling of the Cuban missile crisis and Trump’s response on Tuesday.

“We had a president who was deadly serious and threatening the most horrible possibilities, and that worked,” he said. “In order for Kennedy to be effective, and for Khrushchev to believe that he meant what he said, he had to get the population of the United States to believe it as well. So we did.”

“I’m not saying that Donald Trump now would do that for the purpose of scaring the other side to get a deal, but he’s got to make sure that he’s understood,” he added. “He’s in the same position as Kennedy.”

Ticktin said he felt that Trump’s warning was “appropriate.”

“He’s not doing it because he’s angry or upset,” he said. “This thing going on in Korea isn’t quite as imminent as what happened [in 1962] — people in New York aren’t thinking, ‘Oh my god, a bomb could fall on us at any moment’ — but it could get to that.”

White, however, felt like Trump had drawn the wrong lessons from their time at the military academy.

“The military school environment did teach the fear factor, the aggression factor, the don’t-back-down factor. Absolutely,” said White, who, unlike Trump, joined the Army after graduating and was stationed for a year in Korea.

He called Trump’s warning to North Korea “a pile of bull—t.”

“At the military academy, [General Douglas] MacArthur was our model,” White said. “Trump doesn’t even have MacArthur right. MacArthur wasn’t a warmonger. If it came to that, he would give them holy hell. But if there is no threat of war, don’t threaten war.”

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