The mystery of the missing H-bomb paper

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In the envelope was a six-page document with details of the history of the making of the H-bomb – the new terrifying weapon of mass destruction that only America possessed – and enough up to date technical detail to hugely excite a foreign power. Had he, Wheeler, thought, been burgled by a Soviet agent? When he saw the man had finished, Wheeler darted in and grabbed the manila envelope. Greatly relieved, he returned to his berth and began packing up his suitcase to go. Everything completed, he pulled out the manila envelope for a final double-check on the H-bomb document. To his complete horror, the envelope only contained another, more mundane document – the H-bomb paper had vanished.

A desperate search of his berth and the entire Pullman sleeping car, followed by a frantic tour of Washington’s Union Station rooms and restaurants to try and identify any of his fellow passengers, proved fruitless. An utterly dejected Wheeler had no alternative but to report his loss to the Joint Committee on Atomic Energy (JCAE), three of whose members rushed down to the station to add fresh eyes to the search. But eventually, soon after midday, JCAE executive director William Borden bowed to the inevitable and picked up the phone to the FBI’s Washington office.

In the five weeks that followed, Special Agent Charles Lyons, leading the investigation, was able to identify and rule out as suspects five men who had taken neighbouring berths on the Pullman train Wheeler had travelled in from Philadelphia. But there remained some worrying gaps in his knowledge. Firstly, Lyons was unable to track down an “ordinary, plainly dressed” couple, 30 to 40 years old, and their small child, who had bought a last-minute ticket from the conductor and taken up the lower and upper bunks in berth No 1. Even more tantalising was his failure to find the occupant of lower berth No 8, diagonally opposite Wheeler. Lyons had this individual’s ticket – a last-minute one, bought over the counter in Philadelphia – but frustratingly, the name written on the railroad company’s seating chart could not be identified, despite being pored over in the FBI laboratory in Chicago. This mystery man – or woman – was something like ‘Magenbright’, ‘Wagenbright’, or ‘Wagenknight’ – but no one could be sure which.

What were the contents of the H-bomb paper?

What he read that night remains highly classified, even today. But we can glean something of what it said from Wheeler’s interview with the FBI. The document confirmed that the US was on its way to a successful thermonuclear weapon (it had tested a rough and ready prototype, code-named ‘Ivy Mike’, in November 1952). It also revealed that there were several varieties of the thermonuclear weapon considered to be available for practical use. Wheeler told his inquisitors that the top-secret document also revealed technical details about the making of the ‘super’ fusion bomb – that “Lithium-6 was useful, that compression was useful, and that radiation heating provided a way to get that compression”.

The physicist believed that mention of Lithium-6 as a vital ingredient would have aroused the interest of the Kremlin. But he told FBI investigators that the “qualitative idea of radiation implosion... is the most important revelation” – and could be crucial information for Soviet atomic scientists. Wheeler had a record of carelessness with official documents, but no one seriously believed he was a Soviet spy. As Agent Lyons pursued the case, he first accounted for the movements of all Soviet diplomatic personnel on the morning of 7 January. He then initiated a probe into what he described as a “delegation of radicals” heading for the capital on Wheeler’s train. This was a group bound for the White House where they would carry placards urging the president to commute the death sentence of the Rosenbergs. FBI agents shot numerous still photographs and reels of film of this protest, and made Wheeler study it to see if he recognised any of the individuals from his train journey on 6 and 7 January. But the scientist was unable to provide a positive identification, and that trail went cold.

Fear and paranoia

The loss of the H-bomb document could not have come at a more critical time in the Cold War – and at a more febrile moment in American history. The war in Korea, now two-and-a-half years old, showed no signs of ending. An atmosphere of worry, even paranoia about communists at the heart of the government was being stoked by the witchfinder-in-chief, Joe McCarthy. Then there were the atomic spies, Julius and Ethel Rosenberg, had been tried, convicted and sentenced to death.

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Since the end of December 1952, the couple’s supporters had been holding a continuous picket outside the White House, where they called on President Harry S Truman to grant the couple clemency before leaving office later that month. Now came this disappearance, which could have come right out of the pages of a spy thriller – perhaps from the pen of someone like Ian Fleming, who in 1953 was about to introduce James Bond to the world in Casino Royale.

Eisenhower’s burden

The H-bomb paper could simply have slid away from Wheeler’s grasp as he dropped off to sleep on that Tuesday night, somehow vanishing into the structure, equipment or bedding of the Pullman. But when the newly elected President Dwight Eisenhower had the task of revealing the paper’s disappearance to his National Security Council a month later, most of them were convinced it was the work of the Soviets – none more so than Vice-President Richard Nixon, who urged the FBI to carry out a complete check on each and every member of the JCAE. Eisenhower asked his deputy to liaise with FBI director J Edgar Hoover about taking into ‘custody’ all the committee’s files – before any more papers were lost. Eisenhower’s mood that day was a mixture of deep anxiety and anger that such a calamity should happen so soon on his watch.

Rarely had a president of the United States laid bare his feelings so starkly before his closest colleagues. He frankly confessed that he was “frightened”, and had no idea how to proceed. He expressed bewilderment that the item in Wheeler’s possession had been erroneously labelled as ‘Secret’ rather than ‘Top Secret’, and sent merely by registered mail to a ‘college professor’ in Princeton rather than being escorted to him by armed guard. If those responsible for this disastrous breach of security – the staff of the JCAE – had been in the army, they “should have been shot”, exploded the president. The JCAE would soon have a new chairman and a new set-up, but, as Eisenhower bemoaned, that would simply be to “lock the barn door after the horse had been stolen”.

There was no serious thought given to briefing the British about the loss. As more and more evidence was coming to light about the Cambridge Spies (the British university students recruited by the Soviets in the 1930s), and with the treachery of Klaus Fuchs (the German-born British scientist who had passed on A-Bomb secrets) still raw, there was little collaboration on the nuclear front between Washington and London. Eisenhower had been unimpressed when he had met ageing prime minister Winston Churchill in January, reflecting he was “as charming and interesting as ever – but definitely showing the effects of the passing years”.

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Has the H-bomb paper ever been found?

In the end, after FBI agents all over the eastern side of the United States had interviewed hundreds of people and supervised the search of miles and miles of railway track and dozens upon dozens of railway carriages, they were none the wiser. The hunt petered out and Eisenhower had more immediate day-to-day preoccupations, primarily trying to end the war in Korea. Maybe the H-bomb paper will turn up one day in one of Putin’s files in the Kremlin. What is a fact is that only seven months later, in August 1953, the Soviet Union drew level with the US when it tested its own prototype H-bomb on the steppe in the northeast Kazakhstan.

As for ‘Johnny’ Wheeler, he escaped with a dressing-down from Gordon Dean, chairman of the Atomic Energy Committee: he was too valuable a member of the H-bomb project to be fired. Years later, musing about the incident in his memoirs, Wheeler wrote: “It is interesting, even now, to wonder whether my document was purloined by a Soviet agent. It could hardly have vanished into thin air.”

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Roger Hermiston is a writer and journalist. His latest book is Two Minutes to Midnight: 1953 – The Year of Living Dangerously (Biteback Publishing, 2021)

This article was first published in the December 2021 issue of BBC History Revealed Magazine