(The opinions expressed here are those of the author, a columnist for Reuters.)

LONDON - When U.S. President John F. Kennedy and his national security team discovered the presence of Soviet nuclear missiles in Cuba in October 1962, their priority was to ensure no one outside their circle knew about it until they had decided what to do.

That approach, Kennedy's brother Robert said later, was critical to giving the administration the time and space needed to think clearly.

Only after JFK had decided to blockade Cuba against future weapons shipments and threaten an invasion if the missiles were not withdrawn did he address the nation, with America’s closest allies – Britain, France, Germany and NATO ambassadors – told just minutes beforehand.

According to two newly released books and accompanying articles by their authors, New York Times defence correspondent David Sanger and CNN counterpart Jim Scuitto, the Biden White House concluded that events in Ukraine in October 2022 had created the most dangerous nuclear threat since Cuba.

Once again, they appear to have chosen to handle the situation in part behind the scenes, with the scale of concern only now becoming clear.

What is apparent is that the United States and its allies were engaged in a diplomatic effort to persuade the Kremlin that it might be risking more than it was willing should it look to detonate a tactical nuclear device in Ukraine.

Further details will probably drip out over coming years and decades. What we know so far, however, may already provide something of a guide for how future U.S. administrations handle other crises perhaps fast approaching, whether over Taiwan, Ukraine or along NATO’s eastern European border.

It also helps explain why U.S. and Western officials have not always been enthusiastic about pushing military supplies towards Ukraine. While Washington and its allies remain keen that the Ukrainian government survives and retakes some of its captured territory, they have been nervous that should Ukraine prove too successful it might prompt a dangerous escalation from the Kremlin.

According to chatter picked up by U.S. intelligence services and only now being publicly discussed, senior Russian military commanders in late 2022 were openly discussing the prospect of detonating a nuclear device in Ukraine.

According to Sanger at the New York Times, the CIA warned that if Ukrainian forces overran Russian lines and looked on the brink of retaking the Crimean peninsula, home to Russia's Black Sea Fleet, the prospect Russia might use at least a single atomic bomb could rise to above 50%.

More concerning still, Russian officials appeared to be preparing the ground for such an option by spreading false reports that Ukraine itself was preparing to use a "dirty bomb".

Russia’s ambassador to the United Nations, Vasily Nebenzya, handed the organisation a Russian official letter warning of that threat, while several senior Russian officials including Defence Minister Sergei Shoigu called Western counterparts to convey a similar message, the new books report.

That seems to have got the attention of the White House. During the run-up to Vladimir Putin’s full-scale invasion of Ukraine in February 2022, U.S. President Joe Biden went of his way in several public statements to say that while the United States stood behind its obligation to defend NATO members such as the former Soviet Baltic states, that obligation did not include defending Ukraine from conventional military attack.

 

'ARMAGEDDON' SPEECH

On Oct. 8, 2022, in his most pointed warning to Russia on Ukraine at any point and apparently dubbed the "Armageddon" speech by White House insiders, Biden told a Democratic fundraising audience in New York the situation in Ukraine just over six months after the invasion might be the most dangerous since Cuba in 1962.

While Biden did not brief in detail the threat assessments that are now reported to have been circulating within the Pentagon and White House, he made it clear he felt it possible Putin might turn to nuclear weapons given that his army was “underperforming” – and he came close to implying that any such atomic weapons use might draw in the United States.

"First time since the Cuban missile crisis, we have the threat of a nuclear weapon if in fact things continue down the path they are going," said Biden. "We are trying to figure out what is Putin's offramp? Where does he find a way out?"

Once a single nuclear weapon was used, Biden warned, there might be no turning back. "I don't think there's any such thing as the ability to easily (use) a tactical nuclear weapon and not end up with Armageddon."

In the days around that statement, U.S. Secretary of State Antony Blinken, Defence Secretary Lloyd Austin and National Security Adviser Jake Sullivan all called their opposite Russian numbers with a similar message. A relentless drumbeat of such interactions continued through the autumn. At the end of October, British Foreign Secretary James Cleverly warned: "Nuclear weapons would change the nature of the conflict. There would be severe consequences for Russia."

Neither in public nor private do those precise consequences appear to have been explained to Russian officials – an approach dubbed "strategic ambiguity". Nevertheless, they will have been broadly understood as a threat of either conventional or atomic military action.

Ukrainian President Volodymyr Zelenskiy was blunter still, warning Putin: "He needs to understand that after the use of nuclear weapons he will be unable any more to preserve, so to speak, his life."

 

BROADER IMPLICATIONS

Some of this was widely reported at the time. But without release of the supporting intelligence reported in the books pointing to a potential Russian nuclear first strike against Ukraine, the world avoided the wider “war scare” and market crash or economic downturn that might have accompanied more public discussion.

A similar pattern might follow with future crises – a series of statements in public, accompanied by often even more frenetic behind-the-scenes activity, as well as more overt military posturing.

Whether autumn 2022 really represented the most dangerous point in human history since 1962 remains open to dispute. Even Scuitto, Sanger and the senior U.S. officials they quote acknowledge they never had a solid idea how close Russia might have been to using tactical nuclear weapons that year.

In reality, the latter years of the Cold War – particularly 1983, when the Soviet leadership may have briefly persuaded themselves the West under U.S. President Ronald Reagan might be about to launch a surprise attack – may still have been more dangerous. The scale of that danger, however, also only became clear later.

In this case, how close Putin really was to a nuclear strike may only become clear after he is swept from office – and perhaps not even then. What does seem true, however, is that the wider diplomatic offensive to dissuade Russia from using nuclear weapons may have had an effect. That included warnings from China and India – both close Russian partners – at the November 2022 G20 in Indonesia that there was no place for nuclear weapons used in the modern world.

By mid-2023, it was clear Ukraine’s summer offensive had failed, and that while Kyiv could strike Crimea with missiles, it did not appear to have the ability to seize the peninsula itself.

More recently, Putin has returned to his nuclear rhetoric, warning that significant Western combat forces in Ukraine might lead to a Russian atomic response, an apparent attempt to deter other European NATO nations from following French President Emmanuel Macron in suggesting such a course.

More war scares may be coming – whether in Europe or elsewhere. What is less clear is how many of them the world will notice at the time.

* Peter Apps is a Reuters columnist writing on defence and security issues. He joined Reuters in 2003, reporting from southern Africa and Sri Lanka and on global defence issues. He is also the founder of a think-tank, the Project for Study of the 21st Century, and, since 2016, has been a Labour Party activist and British Army reservist.

(Editing by Nick Macfie)