Venona project
Uncover the secrets of the Venona Project, a top-secret US effort to decrypt Soviet intelligence during WWII and the Cold War.
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<p>The Venona project was a United States counterintelligence program initiated during World War II by the United States Army's Signal Intelligence Service and later absorbed by the National Security Agency (NSA), that ran from February 1, 1943, until October 1, 1980. It was intended to decrypt messages transmitted by the intelligence agencies of the Soviet Union (e.g. the NKVD, the KGB, and the GRU). <br/>During the 37-year duration of the Venona project, the Signal Intelligence Service decrypted and translated approximately 3,000 messages. The signals intelligence yield included discovery of the Cambridge Five espionage ring in the United Kingdom, and also of Soviet espionage of the Manhattan Project in the US, known as Project Enormous. Some of the espionage was undertaken to support the Soviet atomic bomb project. The Venona project remained secret for more than 15 years after it concluded.</p>
<p>Background<br/>During World War II and the early years of the Cold War, the Venona project was a source of information on Soviet intelligence-gathering directed at the Western military powers. Although unknown to the public, and even to Presidents Franklin D. Roosevelt and Harry S. Truman, these programs were of importance concerning crucial events of the early Cold War. These included the Julius and Ethel Rosenberg spying case (which was based on events during World War II) and the defections of Donald Maclean and Guy Burgess to the Soviet Union.<br/>Most decipherable messages were transmitted and intercepted between 1942 and 1945, during World War II, when the Soviet Union was an ally of the US. Sometime in 1945, the existence of the Venona program was revealed to the Soviet Union by cryptologist-analyst Bill Weisband, an NKVD agent in the US Army's SIGINT. These messages were slowly and gradually decrypted beginning in 1946. This effort continued (many times at a low level of effort in the latter years) through 1980, when the Venona program was terminated. The analyst effort assigned to it was moved to more important projects.<br/>To what extent the various individuals referred to in the messages were involved with Soviet intelligence is a topic of minor historical dispute. Most academics and historians have established that most of the individuals mentioned in the Venona decrypts were probably either clandestine assets and/or contacts of Soviet intelligence agents, and very few argue that many of those people probably had no malicious intentions and committed no crimes.</p>
<p>Commencement</p>
<p>The VENONA Project was initiated on February 1, 1943, by Gene Grabeel, an American mathematician and cryptanalyst, under orders from Colonel Carter W. Clarke, Chief of Special Branch of the Military Intelligence Service at that time. Clarke distrusted Joseph Stalin, and feared that the Soviet Union would sign a separate peace with Nazi Germany, allowing Germany to focus its military forces against the United Kingdom and the United States. Cryptanalysts of the US Army's Signal Intelligence Service at Arlington Hall analyzed encrypted high-level Soviet diplomatic intelligence messages intercepted in large volumes during and immediately after World War II by American, British, and Australian listening posts. Frank Rowlett was one of the project leaders.</p>
<p>Decryption<br/>This message traffic, which was encrypted with a one-time pad system, was stored and analyzed in relative secrecy by hundreds of cryptanalysts over a 40-year period starting in the early 1940s. When used correctly, the one-time pad encryption system, which has been used for all the most-secret military and diplomatic communication since the 1930s, is unbreakable. However, due to a serious blunder on the part of the Soviets, some of this traffic was vulnerable to cryptanalysis. The Soviet company that manufactured the one-time pads produced around 35,000 pages of duplicate key numbers, as a result of pressures brought about by the German advance on Moscow during World War II. The duplication—which undermines the security of a one-time system—was discovered, and attempts to lessen its impact were made by sending the duplicates to widely separated users. Despite this, the reuse was detected by cryptanalysts in the US.</p>
<p>Breakthrough</p>
<p>The Soviet systems in general used a code to convert words and letters into numbers, to which additive keys (from one-time pads) were added, encrypting the content. When used correctly one-time pad encryption is unbreakable. However, cryptanalysis by American code-breakers revealed that some of the one-time pad material had incorrectly been reused by the Soviets (specifically, entire pages, although not complete books), which allowed decryption of a small part of the traffic.<br/>Generating the one-time pads was a slow and labor-intensive process, and the outbreak of war with Germany in June 1941 caused a sudden increase in the need for coded messages. It is probable that the Soviet code generators started duplicating cipher pages in order to keep up with demand.<br/>It was Arlington Hall's Lieutenant Richard Hallock, working on Soviet "Trade" traffic (so called because these messages dealt with Soviet trade issues), who first discovered that the Soviets were reusing pages. Hallock and his colleagues, amongst whom were Genevieve Feinstein, Cecil Phillips, Frank Lewis, Frank Wanat, and Lucille Campbell, went on to break into a significant amount of Trade traffic, recovering many one-time pad additive key tables in the process.</p>
<p>A young Meredith Gardner then used this material to break into what turned out to be NKVD (and later GRU) traffic by reconstructing the code used to convert text to numbers. Gardner credits Marie Meyer, a linguist with the Signal Intelligence Service with making some of the initial recoveries of the Venona codebook. Samuel Chew and Cecil Phillips also made valuable contributions. On December 20, 1946, Gardner made the first break into the code, revealing the existence of Soviet espionage in the Manhattan Project. Venona messages also indicated that Soviet spies worked in Washington in the State Department, Treasury, Office of Strategic Services (OSS), and even the White House. Very slowly, using assorted techniques ranging from traffic analysis to defector information, more of the messages were decrypted.<br/>Claims have been made that information from the physical recovery of code books (a partially burned one was obtained by the Finns) to bugging embassy rooms in which text was entered into encrypting devices (analyzing the keystrokes by listening to them being punched in) contributed to recovering much of the plaintext. These latter claims are less than fully supported in the open literature.<br/>One significant aid (mentioned by the NSA) in the early stages may have been work done in cooperation between the Japanese and Finnish cryptanalysis organizations; when the Americans broke into Japanese codes during World War II, they gained access to this information. There are also reports that copies of signals stolen from Soviet offices by the Federal Bureau of Investigation (FBI) were helpful in the cryptanalysis. The Finnish radio intelligence sold much of its material concerning Soviet codes to the OSS in 1944 during Operation Stella Polaris, including the partially burned code book.</p>
<p>Results<br/>The NSA reported that (according to the serial numbers of the Venona cables) thousands of cables were sent, but only a fraction were available to the cryptanalysts. Approximately 2,200 messages were decrypted and translated; about half of the 1943 GRU-Naval Washington to Moscow messages were broken, but none for any other year, although several thousand were sent between 1941 and 1945. The decryption rate of the NKVD cables was as follows:</p>
<p>1942: 1.8%<br/>1943: 15.0%<br/>1944: 49.0%<br/>1945: 1.5%<br/>Out of some hundreds of thousands of intercepted encrypted texts, it is claimed under 3,000 have been partially or wholly decrypted. All the duplicate one-time pad pages were produced in 1942, and almost all of them had been used by the end of 1945, with a few being used as late as 1948. After this, Soviet message traffic reverted to being completely unreadable.<br/>The existence of Venona decryption became known to the Soviets within a few years of the first breaks. It is not clear whether the Soviets knew how much of the message traffic or which messages had been successfully decrypted. At least one Soviet penetration agent, British Secret Intelligence Service representative to the US Kim Philby, was told about the project in 1949, as part of his job as liaison between British and US intelligence. Since all of the duplicate one-time pad pages had been used by this time, the Soviets apparently did not make any changes to their cryptographic procedures after they learned of Venona. However, this information allowed them to alert those of their agents who might be at risk of exposure due to the decryption.</p>
<p>Significance<br/>The decrypted messages gave important insights into Soviet behavior in the period during which duplicate one-time pads were used. With the first break into the code, Venona revealed the existence of Soviet espionage at the Manhattan Project's Site Y (Los Alamos). Identities soon emerged of American, Canadian, Australian, and British spies in service to the Soviet government, including Klaus Fuchs, Alan Nunn May, and Donald Maclean. Others worked in Washington in the State Department, the Treasury, OSS, and even the White House.<br/>The messages show that the US and other nations were targeted in major espionage campaigns by the Soviet Union as early as 1942. Among those identified are Julius and Ethel Rosenberg, Alger Hiss, Harry Dexter White (the second-highest official in the Treasury Department), Lauchlin Currie (a personal aide to Franklin Roosevelt), and Maurice Halperin (a section head in the Office of Strategic Services).<br/>The identification of individuals mentioned in Venona transcripts is sometimes problematic, since people with a "covert relationship" with Soviet intelligence are referenced by cryptonyms. Further complicating matters is the fact the same person sometimes had different cryptonyms at different times, and the same cryptonym was sometimes reused for different individuals. In some cases, notably Hiss, the matching of a Venona cryptonym to an individual is disputed. In many other cases, a Venona cryptonym has not yet been linked to any person. According to authors John Earl Haynes and Harvey Klehr, the Venona transcripts identify approximately 349 Americans who they claim had a covert relationship with Soviet intelligence, though fewer than half of these have been matched to real-name identities. However, not every agent may have been communicating directly with Soviet intelligence. Each of those 349 persons may have had many others working for, and reporting only to, them.<br/>The OSS, the predecessor to the Central Intelligence Agency (CIA), housed at one time or another between fifteen and twenty Soviet spies. Duncan Lee, Donald Wheeler, Jane Foster Zlatowski, and Maurice Halperin passed information to Moscow. The War Production Board, the Board of Economic Warfare, the Office of the Coordinator of Inter-American Affairs, and the Office of War Information, included at least half a dozen Soviet sources each among their employees.</p>
<p>Black Friday<br/>In late October 1948 the Soviets began changing their ciphers one by one in rapid succession. They also stopped the use of UHF radio links from Germany and Austria to Moscow, using (overhead) landline instead. While Navy investigators thought it was a routine systems upgrade others were not so sure and later it was attributed to two Soviet spies: American William (Bill) Weisband, a linguist at Arlington Hall, and Briton Kim Philby in the SIS. <br/>At this time some information was trickling in from US intercepts and rare overflights near the East-West border; but with a dearth in intelligence, not even a hint was received of the North Korean attack (approved by Stalin) on South Korea in June 1950. This led to the approval of Operation Gold in Berlin, a joint CIA-SIS operation to tap into underground telephone cables a short distance across the border in East Berlin; the scheme was based on Operation Silver, a SIS operation in Vienna. <br/>Operation Gold was betrayed to the NKVD by SIS member George Blake even before it started intercepting in May 1955. But to avoid compromising Blake, it was allowed to continue to April 1956, with knowledge of the project kept inside the NKVD.</p>
<p>Bearing of Venona on particular cases<br/>Venona has added information – some unequivocal, some ambiguous – to several espionage cases. Some known spies, including Theodore Hall and Bill Weisband, were neither prosecuted nor publicly implicated, because the Venona evidence against them was withheld.</p>
<p>"19"<br/>The identity of the Soviet source cryptonymed "19" remains unclear. According to British writer Nigel West, "19" was Edvard Beneš, president of the Czechoslovak government-in-exile. Military historian Eduard Mark and American authors Herbert Romerstein and Eric Breindel concluded it was Roosevelt's aide Harry Hopkins. According to American authors John Earl Haynes and Harvey Klehr, "19" could be someone from the British delegation to the Washington Conference in May 1943. Moreover, they argue no evidence of Hopkins as an agent has been found in other archives, and the partial message relating to "19" does not indicate whether this source was a spy.<br/>However, Vasili Mitrokhin was a KGB archivist who defected to the United Kingdom in 1992 with copies of large numbers of KGB files. He claimed Harry Hopkins was a secret Soviet agent. Moreover, Oleg Gordievsky, a high-level KGB officer who also defected from the Soviet Union, reported that Iskhak Akhmerov, the KGB officer who controlled the clandestine Soviet agents in the US during the war, had said Hopkins was "the most important of all Soviet wartime agents in the United States".<br/>Alexander Vassiliev's notes identified the source code-named "19" as Laurence Duggan.</p>
<p>Julius and Ethel Rosenberg</p>
<p>Venona added significant information to the case of Julius and Ethel Rosenberg, making it clear Julius was guilty of espionage, and also showing that Ethel, while not acting as a principal, still acted as an accessory who took part in Julius's espionage activity and played a role in the recruitment of her brother for atomic espionage.<br/>Julius and Ethel Rosenberg also had another connection to a recruit for the Soviets named David Greenglass, who was Ethel's brother and Julius's brother-in-law.<br/>Venona and other recent information has shown that, while the content of Julius' atomic espionage was not as vital to the Soviets as alleged at the time of his espionage activities, in other fields it was extensive. The information Rosenberg passed to the Soviets concerned the proximity fuze, design and production information on the Lockheed P-80 jet fighter, and thousands of classified reports from Emerson Radio.<br/>The Venona evidence indicates unidentified sources code-named "Quantum" and "Pers" who facilitated transfer of nuclear weapons technology to the Soviet Union from positions within the Manhattan Project. According to Alexander Vassiliev's notes from KGB archive, "Quantum" was Boris Podolsky and "Pers" was Russell W. McNutt, an engineer from the uranium processing plant in Oak Ridge.</p>
<p>David Greenglass<br/>David Greenglass, codename KALIBER, was the brother of Ethel Rosenberg, and would be crucial in the conviction of the Rosenbergs. Greenglass was a former Army machinist who worked at Los Alamos. He was originally meant to replace a soldier who had gone AWOL, and lied on his security clearance in order to gain access onto the project. Once Klaus Fuchs was caught, he gave up Harry Gold, who in turn, gave up Greenglass and his wife, as well as his sister and her husband. During their trial, Greenglass changed his story several times. At first, he didn't want to implicate his sister, but when his wife was threatened, he gave up both of them. According to Gerald Markowitz and Michael Meeropol, "In the Rosenberg-Sobell case, the government relied heavily upon the testimony of Greenglass, who pleaded guilty to conspiracy to commit espionage in exchange for a reduced sentence for himself and no indictment or prosecution for his wife, Ruth, who he alleged had aided him in committing espionage. Greenglass testified that he had passed information about the atom bomb to Gold and Rosenberg, who in turn passed it on to the Russians." In the end, Greenglass was sentenced to 15 years but was released in 1960 after serving only nine and a half.</p>
<p>Klaus Fuchs</p>
<p>The Venona decryptions were also important in the exposure of the atomic spy Klaus Fuchs. Some of the earliest messages decrypted concerned information from a scientist at the Manhattan Project, who was referred to by the code names of CHARLES and REST. Fuchs had joined the Manhattan Project at Los Alamos in 1944 where he provided information for the development of a plutonium implosion design. He is also credited with being of great assistance to the creation of a Soviet atomic bomb. Fuchs even gave the Soviets the blueprint for the Trinity device that would be detonated at Los Alamos in July 1945. One such message from Moscow to New York, dated April 10, 1945, called information provided by CHARLES "of great value." Noting that the information included "data on the atomic mass of the nuclear explosive" and "details on the explosive method of actuating" the atomic bomb, the message requested further technical details from CHARLES. Investigations based on the Venona decryptions eventually identified CHARLES and REST as Fuchs in 1949. Fuchs was eventually arrested and tried on March 1, 1950, where he confessed to four counts of espionage and received a maximum prison sentence of fourteen years.</p>
<p>Harry Gold</p>
<p>The Venona decryptions also identified Soviet spy Harry Gold as an agent of the KGB who stole blueprints, industrial fo</p>
<hr/><p><em>Based on Wikipedia article: <a href="https://en.wikipedia.org/wiki/Venona_project" target="_blank" rel="noopener">Venona project</a> – licensed under CC BY-SA.</em></p>
