Donald Maclean Fled to USSR After Washington Embassy Leakage was Traced
By Harlan Pryce ·
Secrets from the Washington Embassy were funneled to Moscow for twenty years by a man the Foreign Office considered a rising star, a betrayal that ended in a sudden flight to the USSR.
The trust of the Foreign Office was used as a shield for two decades of betrayal. In Washington, secrets that shaped the post-war order were handed to the Soviets by a man they believed was one of their own.
Tradecraft is rarely about the brilliance of the spy; it is almost always about the blindness of the handler or the complacency of the security officer. Donald Duart Maclean was not a ghost; he was a "high flying employee of the Foreign Office," as the file's catalogue entry for KV 2/4159 records. He didn't hide in the shadows of the embassy; he operated from the center of the room, where the most sensitive cables were drafted and read.
Washington Embassy Leakage
For those of us who have run assets, the most dangerous man in the building is the one who is too perfect for the job. The public record shows Maclean as a man of rapid ascent: a Third Secretary in Paris by 1938, followed by postings in London and Washington, and eventually the head of the American Department in the Foreign Office. He was the ideal civil servant, which made him the ideal conduit for Moscow.
The security failure here was not a single lapse but a systemic collapse. The catalogue entry for KV 2/4159 states that by 1951, Maclean had been "identified as the source of a leakage from the Washington Embassy some years earlier." In the world of embassy work, a leak from the Washington post is not a mere administrative error; it is a strategic disaster. It means the Soviet Union knew exactly what the British were telling the Americans, and exactly what the Americans were telling the British.
When the Security Service finally began to close in, they didn't find a lone wolf. They found a life built on layered falsehoods.
Curzon and Frazer
Deep cover is a burden that wears a man down, but Maclean managed it with the help of a sprawling set of identities. The National Archives' catalogue descriptions for files KV 2/4159, KV 2/4152, and KV 2/4156 list his aliases with clinical precision: Richard Curzon, Mark Frazer, Percy Maclean, and S Madzoevsky.
These were not just names on a passport; they were the tools used to move information and people without triggering the alarms of the very service Maclean was supposed to serve. The deception extended to his domestic life. The record identifies Melinda Goodlett Maclean, an American and British national, as having her own set of masks: Melinda Marling, Melinda Philby, and Natasha Frazer.
In my experience, a spy with a spouse in the trade is either a liability or a force multiplier. Given the longevity of Maclean's operation, the latter seems more likely. The use of these aliases suggests a level of operational support from the Soviet center that allowed them to treat the British Foreign Office as a subsidiary of the Kremlin for twenty years.
May 1951
The end of the game came not with a quiet arrest, but with a disappearance. The catalogue entry for KV 2/4107 records that Guy Francis De Moncy Burgess—aliases Roger Styles and Jim Andreyevich Eliot—disappeared from London in May 1951. He did not go alone. He fled with Maclean while the latter was under investigation for the Washington leaks.
This was the moment the mask finally slipped. The Security Service’s assessment, as noted in the catalogue records for both Maclean and Burgess, was that both men had been Soviet agents since the 1930s. The timeline is devastating. It means that for the entirety of the Second World War and the dawn of the Cold War, the British government had a mole in its highest diplomatic circles who had been vetted and promoted by the very people he was betraying.
Burgess and Maclean reappeared in Moscow, leaving the Foreign Office to sift through the wreckage of two decades of compromised intelligence. The catalogue entries for KV 2/4157 and KV 2/4153 reiterate the same grim summary: a "high flying" official who spent his career ensuring that the Soviet Union was never surprised by Western diplomacy.
The file's catalogue entry for KV 2/4159 notes the Washington leakage occurred "some years earlier" than 1951, but the specific nature of those compromised cables remains absent from the summary.