23rd – 24th August 1942 – Dieppe – Operation Jubilee – Part I - Dress Rehearsal for Invasion
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23rd – 24th August 1942 – Dieppe – Operation Jubilee – Part I - Dress Rehearsal for Invasion
The plan for a raid on the French coast had taken shape independent of American ambitions for a fully-fledged invasion in 1942, an extension of the idea of commando raids designed to disrupt Axis operation and force them to divert resources away from the Eastern Front. The plan for what became Operation Jubilee began to evolve during the spring of 1942 under the direction of Vice Admiral Louis Mountbatten, but was initiated at the prompting of RAF command, who were trying to take on a more proactive role since the daylight skies over Britain were now secure. This new deployment involved aggressive fighter sweeps over France, those consisting of small groups known as ‘Rhubarb’ and larger squadron level sweeps with supporting bomber intended as bait referred to as ‘Circus’. The merit of these sweeps was questionable as they essentially reversed the advantages the RAF had enjoyed over Britain, now it was RAF pilots who found themselves as POWs when they were shot down and the value of these operations were frequently questioned, being continued largely from the desire to be seen to be doing something rather than simply sitting in their bases. Another problem was that the Luftwaffe was proving difficult to draw into battle and Fighter Command came to believe that better bait was needed. It was believed that a large-scale commando raid would be interpreted as the prelude to an invasion and the Luftwaffe would respond accordingly, offering the RAF the opportunity to engage them and inflict heavy casualties. It was dubious logic on which to risk the lives of so many soldiers, but Mountbatten embraced the plan with enthusiasm [1].
Mountbatten had enjoyed considerable success in the planning and execution of other raids, most notably the St. Nazaire raid that successfully destroyed the dry dock there using an explosive laden destroyer and he was something of a favourite of Churchill’s because of this swashbuckling spirit. This did not endear him to other senior officers, including Alanbrooke, and they sought to limit the scope of his operations, Jubilee was an especial target of their ire.
Bomber Command was deeply unhappy about the prospect of being expected to support such an operation, feeling that they would yet again be acting as bait to draw out the Luftwaffe. The Royal Navy was likewise reluctant to commit its capital ships in the fire support role, for much the same reasons. This was a serious impediment given the proposed scale of the attack and there were repeated suggestions that the plan be dropped, at least until after the completion of operations in Sicily Given that Churchill and Mountbatten were determined to press ahead this lack of co-operation had the potential to lead to disaster for the Canadian troops who were now earmarked for the plan. What changed the fortunes of Jubilee was that it drew the interest of the Americans, who saw it even more ambitious terms than Mountbatten and Churchill. To President Roosevelt and his Chiefs of Staff Dieppe seemed a far more attractive option than Sicily in terms of taking the war to the Axis. Dieppe was regarded as a raid by the British, but in Washington it was seen as a springboard for reviving Operation Sledgehammer, the American plan for an invasion of France in 1942. The British had successfully argued that Sledgehammer should only be regarded as a contingency plan in the event of an imminent Soviet collapse and the consensus was that a full invasion could not realistically be carried out until 1943, this had originally been called Operation Roundup and would in due course be renamed as Operation Millennium [2].
Not everyone was convinced that the obstacles to an invasion in 1942 were insurmountable and there was increasing nervousness in Washington about what would happen when the Germans launched a fresh offensive in the east and the wisdom of a contingency plan that might be enacted far too late. Even if the Soviets didn’t collapse there was the fear that Stalin might make a separate peace if the Western Allies didn’t open the ‘second front’ sooner rather than later, and Sicily was too far from Berlin to qualify. Also, after the demise of Mussolini there was a feeling that Sicily was almost as sideshow, with many expecting that the collapse of Italy was all but inevitable regardless of what the Allies did. This led to the Americans offering to join Operation Jubilee as full partners, with the implicit understanding that this was quid pro quo for their support of the Sicilian campaign and that the Allies should make preparations to exploit a successful assault on Dieppe. This meant significantly expanding the scope of the operation, forcing Bomber Command and the Royal Navy to provide far more support than they had originally intended as stinting on support for Jubilee now risked angering the Americans, and if things went badly because of a lack of air or naval support it could have serious consequences for the trans-Atlantic relationship [3].
Having pushed the British into prioritizing Operation Jubilee the US now had to show its commitment was in earnest and provide a force equivalent to that provided by the British, or more accurately the Canadians whose 2nd Infantry Division would be committed to the operation along with the 14th Army Tank Regiment. The contribution from the British Army would take the form of several Commando units, who would be assigned secondary tasks apart from the main attack on Dieppe itself. The major constraint on the American contribution was the availability of shipping and landing craft, which were also in demand in the Pacific as preparations were being made for Operation Watchtower, not to mention Operation Malamute, the invasion of Sicily. The Landing Craft Tank (LCT) was in particular demand and available in limited numbers, meaning that only so much armoured support could be deployed for Dieppe. Regardless of how ambitious the Americans might be about exploiting Dieppe their initial landing force would mirror that of the Canadians, one infantry division with elements of one tank regiment in support.
The US Army selected the 9th Infantry Division to take part in Operation Jubilee, under the command of Maj. Gen. Manton S. Eddy, and they would be supported by the tanks of the 1st Battalion of the 66th Armor Regiment, operating a mix of M3 Stuart and M3 Lee tanks during Operation Jubilee. Both were well regarded formations, however like the rest of the US Army forces assigned to Europe it lacked combat experience. Overall, it was a powerful formation and would enjoy air support from the VIII Bomber Command, the predecessor to 8th Air Force. Naval support would fall largely on the Royal Navy, with several warships belonging to the Free French forces were also attached to the naval force [4].
While the plan for Operation Jubilee had expanded beyond the original intention to draw out the Luftwaffe the underlying assumption that the Germans would respond to any apparent landing attempt in force also highlighted its most significant flaw. The Germans were indeed extremely worried about the possibility of an Allied attack on the continent and were doing their best to monitor British ports and gather intelligence on Allied intentions. The latter effort had depended heavily on French double-agents, willing to pass on questions and requests raised by the British to their German handlers. Since Operation Anton and the total occupation of France this source of information had dried up. Several of these agents had chosen to disappear, others had revealed the truth to the British and one or two had taken to passing disinformation to the Germans without involving the British. This meant that as the British tried to gather more detailed information about the conditions in and around Dieppe the Germans remained uncertain about where an attack might take place, which was an advantage the troops taking part in Jubilee would desperately need. On the other hand, they were certain that an assault was coming since it was impossible to disguise the gathering of Allied shipping in the ports of Southern England and the Wehrmacht did its best to mobilize in response. Their reserves had to be placed to react to attacks on any one of several targets and the availability of formations was limited by the developing situation in the East and the increasing anxiety about the reliability of the Italians [5].
That the target of Operation Jubilee had only been kept from the Germans by the disenchantment of French double agents speak to the paucity of Allied intelligence and counter-intelligence efforts in the run up to the Dieppe raid. Not only did the French agents provide the only effective disinformation effort for Jubilee there was a remarkable lack of knowledge about the state of the beaches. The vital question of how well the tanks would cope with the shingle beach was addressed by an assessment based on nothing more than holiday postcards and guesswork [6]. The attachment of new A22 Black Prince tanks outfitted with equipment intended to help Allied armour cross the beaches was all well and good, however this equipment was new, and it was receiving a field trial under the worst possible conditions. It proved fortuitous for the conduct of the battle that the Canadians had insisted on retaining many their homegrown Wolverine tanks [7]. Operation Jubilee still had the potential to turn into a disaster, regardless of the expanded resources that came with US involvement, and everything would come down to the British, Canadian, and American troops fighting on the ground to prevent it doing so [8].
[1] So not the most auspicious origin for Dieppe, which explains a lot about OTL.
[2] With no desperate struggle in the Middle East the Americans are less inclined to just focus on the Med and a lot more interested in Jubilee than they were OTL.
[3] The Americans have muscled their way into Jubilee, meaning that some of the OTL deficiencies are being addressed.
[4] Basically the US troops are forces that would have been part of Torch, which much of the rest of the Torch troops deployed for Sicily.
[5] Thanks to the earlier Case Anton the Germans have lost a lot of the intelligence sources they had OTL, also as you may have noticed Jubilee hasn’t been cancelled and remounted. Owing to the larger scale it took longer to assemble.
[6] Yes really holiday postcards.
[7] The Wolverine will be adding one more battle honour to its service record.
[8] And the battle starts in the next update.
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