by Tom Mahon
Decoding the IRA
Without the Army Ireland cannot gain her freedom
Frank Aiken referring to the IRA, 1925
TOM MAHON & JAMES J. GILLOGLY
MERCIER PRESS
Cork
www.mercierpress.ie
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CMD BookSource,
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Blackrock, County Dublin
© Tom Mahon & James J. Gillogly, 2008
ISBN: 978 1 85635 697 8
10 9 8 7 6 5 4 3 2 1
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Contents
Key Characters
Introduction
Chapter 1: Breaking the Ciphers
Chapter 2: The IRA’s system of communications
Chapter 3: A New Leadership: 1926–1927
Chapter 4: The IRA’s local units
Chapter 5: Intelligence
Chapter 6: The IRA in Britain
Chapter 7: The IRA in America
Chapter 8: The Soviet Union and China
Conclusion
Epilogue
Appendix 1: Organisations, groups and technical terms
Appendix 2: The Mystery Woman
Notes
Bibliography
Acknowledgements
Other Interesting Books
DEDICATION
This book is dedicated to my sister Rosemary and mother Mary In memory of Tom Crofts and his comrades of Cork 1 Brigade
Tom Mahon
To the late William G. Sutton, my long-time cryptographic collaborator and friend, who was always ready to test and suggest new approaches as I developed the cryptanalytic tools I used to break these ciphers.
Jim Gillogly
Key Characters
Aiken, Frank: IRA chief of staff, April 1923 to November 1925. He supported Éamon de Valera and was a founder member of Fianna Fáil in 1926.
Cooney, Andy: also known as ‘Mr Smith’. IRA chief of staff from November 1925 to spring 1926, and chairman of the Army Council from November 1925 to January 1927.
de Valera, Éamon: president of Sinn Féin and of the shadow republican ‘government’. In early 1926 he resigned from both positions and founded Fianna Fáil.
Devoy, John: veteran Irish-American ‘Fenian’ leader, who supported the Free State and opposed both de Valera and the IRA.
George: also known as ‘HS’. IRA Officer Commanding in Britain from the autumn of 1926 through 1927. Worked closely with the Soviet agent ‘James’. He was likely George Power, an IRA intelligence officer originally from Cork.
James: pseudonym for a Red Army intelligence agent in London. The IRA supplied him with information in return for payment.
Jones, Mr: pseudonym, also known as JB. An IRA secret agent in New York, who worked for Soviet intelligence.
Lynch, Liam: IRA chief of staff during the Civil War, from 1922 until his death in April 1923. Moss Twomey’s mentor.
MacBride, Seán: also known as ‘Mr Ambrose’. An IRA leader closely allied with Moss Twomey. He travelled extensively on the continent, where he was in contact with Soviet agents.
McGarrity, Joseph (Joe): chairman of Clan na Gael. The most important IRA supporter in America.
Neenan, Connie: also known as An Timthire. The official IRA representative in the US.
O’Donnell, Peadar: member of the Army Council and editor of the IRA’s paper, An Phoblacht. He was the leading IRA republican socialist intellectual and also a distinguished novelist.
Russell, Seán: IRA quartermaster general, in charge of weapons and explosives. He was the leading militarist in the organisation and was dismissive of any political involvement by the IRA.
Sheehy, John Joe: captain of the Kerry football team and commander of the Kerry IRA.
Stephen: pseudonym for the Red Army intelligence agent in America who was in contact with the IRA.
Twomey, Maurice (Moss): also known as ‘Mr Browne’. Succeeded Andy Cooney as chief of staff in the spring of 1926 and in January 1927 was also appointed chairman of the Army Council. He remained chief of staff until 1936 and was one of the most influential of the IRA’s leaders.
NOTE:
The text which was originally in the IRA’s secret code or cipher, is printed in a typewriter type font. For example: Let me know [the] names of [the] prison officials against whom action should be taken.
Introduction
Tom Mahon
Try and get formulae for these tear gases and mustard gases and [an] idea of [the] plant necessary [for production].
IRA chief of staff to agent in America
Could you get some mines or incendiary bombs put on ships or put ships on fire with petrol or other inflammables?
Moss Twomey, IRA chief of staff, to the IRA in Liverpool
In 2001 I was researching a (still unfinished) project at the University College, Dublin (UCD) Archives when I came across a number of IRA documents from the 1920s that were written in a secret cipher or code. At the time, I didn’t think much about them and continued with my research, but every now and then I’d find another such document and slowly my curiosity grew. Eventually, three years later I started to gather them together (with the help of the principal archivist Seamus Helferty and his staff) and set out to have them decrypted. I eventually met up with James Gillogly, one of the leading civilian cryptologists in the world, and this book is the result of James’ decryptions of these documents – a world of espionage and intrigue never before described.
This is the IRA for the first time, in its own uncensored words – no topic is omitted and there is no attempt to present a sanitised image for public consumption. This is the complete IRA network – operations, arms smuggling, disputes and retaliation. A story with spies, Russian agents, clandestine meetings and poison gas – it is part James Bond and part Walter Mitty. The tenor of the documents ranges from ruthlessness to pathos and often with a dash of humour. The strength and ingenuity of the IRA is revealed alongside its incompetence and the widespread demoralisation of its members.
In all James decrypted 312 documents written in cipher. The IRA encrypted them so they would remain secret to all except the intended recipients and they were concerned about seizure by the police. To the best of my knowledge, they have never before been decrypted for publication.
I found the documents among the tens of thousands of papers donated to UCD by the family of Moss Twomey, IRA chief of staff from 1926 to 1936. The encrypted documents represent the most highly classified correspondence between the IRA’s General Headquarters (GHQ) in Dublin and its units and operatives. These include units throughout Ireland and Britain, prisoners in jail in Ireland and agents in Britain and America. Some of them contain only a name or address in cipher, others have several pages of densely typed secret text. The despatches to America are the longest, as Moss Twomey had no other way to keep in contact with his representatives there. The vast majority of these documents were dated 1926 or 1927, with a few from either 1925 or 1928.
The cipher is easy to distinguish from ordinary English (or plain text) – frequently consisting of blocks of five letters with no overt meaning. For example, Moss Twomey sent a message to the IRA in Liverpool: UEIRS, NRFCO, OBISE, IOMRO, POTNE, NANRT, HLYME, PPROM, TERSI,
HEELT, NBOFO, LUMDT, TWOAO, ENUUE, RMDIO, SRILA, SSYHP, PRSGI, IOSIT, B. When decrypted this read: Could you get some mines or incendiary bombs put on ships or put ships on fire with petrol or other inflammables?1
This order was written in 1927, but was dated 1924. This was deliberately done to confuse the police in the event of capture of the document.
THE MAJORITY OF THE documents were written in a transposition cipher, meaning that the individual letters of the original (plain text) message were rearranged. A significant minority of the documents used a substitution cipher, where letters were replaced by assigned letters or symbols. A cipher is different from a true code where the original text is replaced by assigned words, phrases or sentences rather than by individual letters.2 When I first rounded up samples of the documents and brought them back to my home in Hawaii, there were two questions on my mind. Could they be decrypted? What story would they tell? It seemed to me that a cipher dating from before the time of the German Enigma cipher machines of the 1930s and 1940s could be broken. But at the time I had no appreciation of the challenges that decryption would present.
Figure 1. Moss Twomey wrote to the OC of the IRA’s Liverpool company: Your intelligence officer reports shipments from there for China. If you can do your utmost to destroy any ammunition or other armament or stores being sent. Could you get some time mines or incendiary bombs put on ships or put ships on fire with petrol or other inflammables? Keep this absolutely secret. Do not discuss it. Either carry out the operations or say nothing about it.
When the ciphers were composed, they were encrypted by the sender and then decrypted by the recipient, both of whom possessed a common secret word or keyword (also known as the key). The keyword was any agreed word of moderate length such as ‘imprisonment’ or ‘determination’. In most cases, the keywords were no longer known and even if I had the original keyword, I did not know how the cipher was constructed around the key.
In my quest to decipher the documents, I started with a search on Google, which did not turn up much of promise. I then talked to a colleague at work who was a reserve officer in the US army, and he made some inquiries of fellow officers who worked in intelligence. Understandably they were reluctant to use government computers, and time, for any unauthorised project. Next, I contacted a professor in the department of mathematics at the University of Hawaii. He had spent some time as a post-graduate student studying cryptology and instantly recognised them as a form of cipher called columnar transposition. However, even with this insight I was no closer to unlocking the secrets.
Hoping for a lucky break I continued to surf the web. Among the sites I looked at was that of the CIA; then late one evening I came across the National Security Agency (NSA) website. The NSA is one of the most secret and important security agencies in the United States. It is the main centre for cryptanalysis in the country, with responsibility for collecting and analysing signals intelligence from around the world.3 The website included a section on the history of cryptology; I sent an e-mail titled ‘history’, explaining my dilemma.
A little later the NSA replied that they couldn’t help but recommended I contact the American Cryptogram Association. I sent the association a sample of six brief ciphers, which Dave Smith kindly shared with the association’s membership by e-mail. Exactly two hours later (to the minute) the solutions came back to me courtesy of Dr James Gillogly. One was a message on importing explosives to Ireland from Britain, while others talked of secret meetings. At last, I was on to something – or rather James was!
James became my new partner and together over the next three years we tried to reveal the secrets of the IRA. I corresponded with him by e-mail for a few years before we actually met face to face. In the meantime, I discovered that I had stumbled across one of the most brilliant cryptologists in the US. A quiet-spoken man, he approached each new cipher as a complex but logical word puzzle.
James had been fascinated with ciphers since his days as a cub scout, when his father challenged him and his brother with simple letter substitution ciphers. At university he majored in computer science, and in 1978 received a PhD from Carnegie-Mellon University. At that time he wrote TECH – one of the early computer chess programmes – with the aim of pushing forward the frontier of computer technology in the realm of artificial intelligence. TECH went on to take second place in a world computer chess championship and pioneered some of the search techniques used by Deep Blue, which in 1997 became the first computer programme to defeat a world chess champion, Garry Kasparov.
In 1977, James made his first break of a previously unsolved cipher – a vellum page with odd symbols from the reign of King Henry VI (1421– 1471) of England. It turned out to be an alchemical formula beginning ‘take 1 ounse of your gold tat is desoluid and chaue 22 …’ To the best of my knowledge neither James nor his family have since made gold from base metal! Many other successes followed. The most famous of these was his decryption in 1999 of most of the cipher embedded in sheets of copper on the kryptos sculpture in a courtyard at the CIA headquarters in Langley, Virginia. Kryptos is a Greek word that appropriately means ‘hidden’. James also worked on German codes from the Second World War which had been encoded by the Enigma machine and his method was used to break a number of previously unbroken messages from the war.
Over the years, he went on to found a software company with his wife Marrietta and to develop network security programmes for computer operating systems. Since his retirement in 1999, he has acted as a consultant to the FBI and designed software to support law enforcement cryptanalysts combating criminals and gangs who use cipher, including gang members communicating with their imprisoned colleagues.
Working on the IRA documents, James delighted in beating the IRA cryptographers, without having the need for the original keywords. He performed the decryptions by loading the cipher text onto his computer and then analysing it with highly sophisticated decryption software that he had developed himself. Several times, he deciphered messages that the original recipient had complained could not be decoded – messages where the wrong keyword was used or the numbering of the encrypted letters was incorrect. On occasion, he was able to decrypt messages where a part of the document had been damaged or torn. This is possible with transposition ciphers as the letters for each word are distributed throughout the text, whereas in plain text all the letters of a word are together in sequential order. Thus if the corner of a cipher document is torn off and a block of letters missing, there may still be most of the letters of each word available, allowing one to deduce the actual message. However, with plain text if a word is missing there are no components of it in the remaining portion of the document.
While I was interested in the contents of the cipher, James revelled in this great puzzle and the variety of encryption and security techniques used by the IRA.
Over the course of several trips back to Ireland, I was able to accumulate the 300 or so documents with cipher, in addition to a large number of papers containing supporting or background information. This work was largely done at UCD Archives in Belfield, Dublin, one of the premier repositories of documents covering twentieth-century Irish history. The Twomey Papers and the Ernie O’Malley Papers, both housed in the UCD Archives, are among the most important primary sources relating to the IRA. These, and other, collections make the IRA perhaps the most comprehensively documented revolutionary group of the twentieth century.
Copies of the documents arrived at my home in Honolulu, Hawaii, where I copied them again, sorted them and forwarded them to James in Los Angeles. On receiving the decryptions back from James I tried to assemble the cryptic messages into a coherent narrative within the appropriate historical context.
The world described by the papers was difficult to comprehend at first. We were getting seemingly unrelated snippets of information. Few of the messages were understandable on their own without reference to other documents or without knowledge of the background in which the events described were taking place. It was
rather like assembling a large jigsaw without a picture on the box. And at the beginning it seemed like all we had were a few blue pieces that could have been either sky or ocean!
For security purposes the IRA were deliberately indirect and cryptic, even in cipher. For instance, only rarely were IRA leaders or key agents referred to by their real names; instead they were assigned a pseudonym or referred to by rank. So we were left with a list of fictitious names – Mr Brown, Mr Smith, Mr Ambrose and Jack Jones. By cross referencing with multiple documents and correlating the movements of the characters with those of known IRA leaders I was eventually able to find out the real name behind many of the pseudonyms and make a probable guess at some of the others. In the case of unsigned letters, it was often possible to credit them to a particular author by their reference number, cross-referencing to other papers or by looking at subsequent letters acknowledging receipt of the original letter.
‘Mr Brown’ (or Browne) and ‘Mr Smith’ at GHQ oversaw most of the correspondence with the IRA’s agents in America. So it seemed likely that they represented Moss Twomey and Andy Cooney, the IRA’s two key leaders. From the cipher, we learned that ‘Mr Smith’ had recently returned from a visit to America and later went to England to complete his studies. This fitted the profile of Cooney, who visited America in the summer of 1926 and resigned as chief of staff so he could complete his medical studies and qualify as a doctor. The proof finally came in a security lapse by Moss Twomey when he wrote to Connie Neenan in America: ‘send Cooney [a] copy of the addresses he had [in the US]’. But then in the précis (or plain text summary of the cipher that was kept on file at GHQ) he made the error of writing: ‘send address to Smith’. Twomey should have written ‘Smith’ in both cipher and the précis. This slip-up confirmed that ‘Mr Smith’ was a cover for Andy Cooney.4
