Nonetheless, once a foothold was established, in order to bring the necessary supply line into play in time, access to a port or ports would be necessary. Only there were none in Normandy. Cherbourg had been identified and targeted but realistically – militarily – it would take time to seize. Normandy as a landing site for the invasion had the disadvantage of not having port facilities available, and the planners toiled over this dilemma until they imaginatively – and initially it seemed far-fetched – suggested bringing the harbour with them. Making that idea a reality became the work of John Desmond Bernal from Nenagh, County Tipperary, a scientist and Professor of Physics at Birkbeck College, London. At the outbreak of the war, Bernal joined the Ministry of Home Security and began working on proposals for ‘artificial harbours’. He was convinced of the necessity for such ‘floating harbours’ and persuaded Churchill of the need for them and that he could contribute to making them a reality. He suggested these could be prefabricated in sections and towed (slowly) across the Channel, then carefully positioned and sunk so that the upper sections of their reinforced concrete caissons could support, above water level, piers along which ‘roadways’ leading to the beaches could facilitate the rapid offloading of supplies. Similarly constructed floating breakwaters and scuttled merchant navy ships provided protection from wind, waves and bad weather. Codenamed ‘Mulberry’, two floating harbours were constructed requiring huge amounts of resources (including concrete from Drogheda, County Louth), a large workforce and effort. ‘Mulberry A’ was for use by the Americans on Omaha Beach at Saint-Laurent-sur-Mer and ‘Mulberry B’ was for use by the British and Canadians on Gold Beach at Arromanches-les-Bains. The Merchant Navy ships scuttled to act as breakwaters were codenamed ‘Gooseberries’.
Shore to ship, then ship to shore, Operation Neptune was the naval element of Operation Overlord and it was at the High Water Mark of Ordinary Spring Tides (HWMOST) that was regarded as the established point at which the naval responsibility for the assault ceased and that of the army commenced. Warships and transport ships (including landing craft), mostly in the first wave, would be joined by supply ships and more transport ships. The warships provided naval gunfire support on the invasion and later to disrupt German counter-attacks on the beachhead. The bombardment of the beaches included counter-battery fire against German shore artillery. John Joseph Taft from Booterstown, Dublin, Royal Navy, was to be lost off the Normandy beachhead in the summer of 1944. His brother Anthony (18) was one of the very first Irish victims of the war on board the aircraft carrier HMS Courageous, on which were some three dozen or so Irish crew. The Courageous was torpedoed and sunk by German submarine U-29 on 17 September 1939 off the coast of Ireland, going down with more than 500 (519) of the crew.
The vast armada of Operation Neptune, the amphibious invasion fleet of over 6,000 (6,330) ships, had to be protected from German submarine U-boats and surface E-boats. Operation Cork, a plan to prevent U-boat packs setting sail from Brest and their bases in the Bay of Biscay and reaching the D-Day landing and support convoys was launched, whereby a 20,000 square mile area of sea from the south coast of Ireland to the mouth of the River Loire was subdivided into twelve overlapping areas, each one patrolled every thirty minutes by depth-charge dropping anti-submarine planes from Coastal Command. This would force the U-boats, known to have concentrated in their bases in anticipation of an invasion, to run submerged, deplete their batteries and reduce their top speed. In the event, fifteen U-boats set sail from Brest on the afternoon of D-Day followed by others from the Bay of Biscay. Twenty-two sightings were made by Coastal Command and over the next six days, six U-boats were sunk and six badly damaged. Their commander withdrew the remainder and no loss due to U-boats was recorded by the D-Day fleet for the entire month of June. Other forms of protection of the D-Day preparations were made to ensure that Operation Overlord remained a secret. Civilian travel between Britain and the Republic of Ireland (Éire) was stopped and a belt of coastline to a depth of ten miles (16 km) from Land’s End to the Wash was sealed off to the public.
War is organised confusion, and Operation Overlord was highly dangerous and its outcome far from certain. Despite the views of the Allied ‘Bomber Barons’, Harris and Spaatz, wars can only be won on the ground, and one of the ways to cope with some of the confusion that war brings is to sow seeds of confusion yourself. Actuality and deception are powerful agents, especially combined with surprise, delivered with purpose, pace and precision. To achieve surprise and confusion, deception had to be deployed. The Allies mounted a programme of deception to convince the Germans what their methodical minds and logical thinking would rationally make them believe – that the invasion would be landing at Pas-de-Calais. Operation Fortune created a dummy army on the south east coast of England complete with dummy tanks, planes and ships. They created ‘an army that never was’ led (thus adding to the delusion) by a very real, well-known leader: Lieutenant General George S. Patton.
The First United States Army Group (FUSAG), with eleven divisions (150,000 men) were the main characters in this ‘pantomime of pretence’. A false force, facilitated by a fake network of radio traffic and information supplied by agents who had been ‘turned’ and were now double agents, in fact working for the British as part of the Double Cross System (XX System) fed fictional intelligence through a completely imaginary network of agents. One agent in particular, codename ‘Garbo’, created a network of twenty-seven fictional agents, all providing information to German intelligence that the Allied invasion force would land much further up the coast than the Normandy beachhead. The aim was to keep the Germans convinced enough to weight their main defence effort opposite Pas-de-Calais, both for the D-Day landings itself and thereafter. Indeed, Allied planners believed that this fiction could be maintained even after the landings had taken place and that the Germans would believe that the Normandy landings were a feint, a diversion and Pas-de-Calais would witness the Allies’ mass effort, and so the German Army would keep the bulk of their forces and tanks fixed there and away from Normandy, and not be involved in the counter-attacks on the Allied Normandy bridgehead.
To ensure they were not being triple crossed, the Allies were able to confirm their misinformation campaign was working because cryptographers at Bletchley Park had broken Germany’s highly complex, supposedly impregnable, Enigma code, a stunning achievement for the Allies in their intelligence war. What is little known is that the Irish had a German codebreaking cell all of their own, led by Dr Richard J. Hayes from west Limerick. Hayes, the Director of the National Library, was a totally unassuming and mild-mannered man, albeit a colossus in cryptography. Colonel Dan Bryan, the head of Ireland’s intelligence service, G2, led the secret counter-intelligence war to decode wireless messages being covertly transmitted through Morse code from a house in north Dublin owned by the German Embassy. Hayes had been seconded to Colonel Bryan’s counter-intelligence programme during the Second World War for his intellectual prowess. Speaking several languages, including fluent German, Hayes was also a highly skilled mathematician.
He worked for months each day after completing his own work at the National Library, cycling to McKee Barracks on Blackhorse Avenue, trying to solve the ‘Goertz Cipher’ – an intricate, highly convoluted cipher similar to a code that had baffled staff in Bletchley Park. Such was its importance that the British Intelligence Service MI5 had an entire section of sixteen staff working on breaking it. However, some of the greatest code breaking minds there remained stumped. It was a code used by German spy Dr Hermann Goertz, who having been parachuted into County Meath in Ireland was detained by the Irish police (Gardaí) and held in Arbour Hill Prison where he was visited weekly by Dr Hayes. During one such visit, Hayes tricked Goertz into getting an X-ray, in the course of which he took the opportunity to search through Goertz’s trouser pockets and found his cipher, proceeding thereafter, following months of effort, to crack it. He and Colonel Bryan intercepted messages from the spy and sent their own messages back to hoodwink and outwit him into revealing more information. This was then passed on to Bletchley Park. This quiet campaign contributed in no small measure towards winning the longer war.
The plan revised, the programme of deception well under way, and the provision of necessary supplies had now opened the possibility of a surprise attack, and so the opportunity for success. However, opportunity is only as great as the use made of it and it must be grasped before circumstances