Review of codebreaker by Marc McMenamin

Historian and documentarian Marc McMenamin’s first book, Codebreaker, tells the story of Dr. Richard Hayes, the long-time Director of the National Library of Ireland, and his work assisting Irish military intelligence (G2) as a cryptanalyst and interrogator during World War II. The book is less a biography of Richard Hayes, than a treatment of the efforts of German military intelligence (the Abwehr) to influence the Irish Republican Army to ally with the Germans to expand the war against the British into Ireland. It covers quite well the Irish government’s response to the German espionage threat and the continuing threat of the radical members of the Irish Republican Army (IRA). Hayes was an integral part of G2’s response to the incursion of German spies into Ireland during the war. From the outset of World War II, Nazi Germany sought to open a second front against Great Britain through Ireland. The British were using Northern Ireland as a staging ground for both army and naval forces, and the Americans would do the same after they joined the conflict. The State of Ireland, headed by Prime Minister (Taoiseach) Eamon De Valera had declared its neutrality in the conflict early on. However, that did not mean that there was no conflict in Ireland itself. One opening the Nazis hoped to exploit was the continuing presence of a radical part of the Irish Republican Army that was conspiring against both the government of Ireland, and the British. The Nazis hoped to use the IRA as a destabilizing force within Ireland and as a terrorist organization to undermine and sabotage British rule in the north. To this end, the Abwehr plotted to insert German spies into Ireland to connect with the IRA, arrange to supply them with weapons and explosives, and use them as allies in a possible invasion of either Northern Ireland, the State of Ireland, or both. The German spies who were dropped into Ireland by parachute or put on shore via U-boat were generally incompetent. All but two of them were arrested within 48 hours of their illegal arrival in Ireland. Their associates in the IRA were slightly more capable, but still not up to the caliber of spies portrayed in either literature or in military history books. The most interesting thing about this book is the revelations about the lengths that members of the IRA were willing to go in order to get the British out of Ireland and to disrupt the Irish government. At least one faction of the IRA was nearly constantly trying to convince the Nazis to supply them with arms and ammunition and were