I have been reading the recent biography of the British CIGS Alanbrooke, and been struck by the clear and concise explanation of the differences between the British and Americans over the “second front” in Europe, and when it could be.

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A plan put together for the incredibly unlikely event of sudden German collapse, was Sledgehammer. This was the understanding of Sledgehammer adopted by most Americans. A very limited offensive by very inadequate forces, which could only succeed had Germany already gone close to collapse. Given the circumstances this was somewhat delusional, but it never hurts to plan for eventualities, and the British were happy to go along with this sort of plan.

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Any attempt at Sledgehammer would of course have failed. The German army had not yet been bled dry on the Eastern front, and the Luftwaffe was still a terrifying force which could be (and regularly was) easily moved from Russian mud to Mediterranean sunshine and back again in mere weeks. Even ignoring the opposition, the British were gloomily aware that the Americans had not a clue of the complexities of such a huge amphibious operation. At the time of discussion – May 1942 – the British were using their first ever Landing Ship Tanks and troopships equipped with landing craft to launch a brigade-size pre-emptive operation against the Vichy French on Madagascar. (Another move many historians think was useless. But coming only months after the Vichy had invited the Japanese into Indo-China – fatally undermining the defenses of Malaya – and the Germans into Syria, it was probably a very sensible precaution. Certainly Japanese submarines based in Madagascar [could] have finally caused the allies to lose the war at sea!)

The British deployed two modern aircraft carriers, and a fleet of battleships, cruisers, destroyers and escorts and a large number of support ships, on this relatively small operation. It was the first proper combined arms amphibious operation of the war, and was very helpful to the British to reveal the scale of amphibious transport needed for future operations. By contrast the US Marines hit Guadalcanal six months later from similar light landing craft, and with virtually the same Great War-vintage helmets and guns that the ANZACS had used at Gallipoli. Anyone who reads the details of the months of hanging on by the fingernails at Guadalcanal against very under-resourced Japanese troops, will be very grateful that the same troops did not have to face veteran German Panzer divisions for several years.

So I do not know of any serious historian who imagines that an invasion of France in 1942 could have led to anything except disaster. There are no serious generals who thought it either. (Only Marshall and his “yes-man” Eisenhower consistently argued that it might be possible. And Eisenhower later came to realise – when he was in charge of his third or fourth such difficult operation – that his boss was completely delusional in his underestimation of the difficulties involved. See Dear General: Eisenhower’s Wartime Letters to Marshall for Eisenhower’s belated attempts to quash Marshalls tactical ignorance about parachute drops and dispersed landings for D-Day.)

In practice no matter how much Marshall pushed for it, only British troops were availabe for such a sacrificial gesture, and the British were not unnaturally reluctant to throw away a dozen carefully nurtured and irreplaceable divisions on a “forlorn hope”, when they would prefer to save them for a real and practical invasion … when circumstances changed enough to make it possible.

Unfortunately Roosevelt told the Soviet foreign minister Molotov that “we expect the formation of a second front this year”, without asking even Marshall, let alone wihtout consulting his British allies who would have to do it with virtually no American involvement. The British Chiefs of Staff only had to show Churchill the limited numbers of landing craft that could be available, and the limited number of troops and tanks they could carry, to make it clear that this was ridiculous. Clearly this stupidity was just another example of Roosevelt saying stupid things without asking anyone (like “unconditional surrender”) that did so much to embitter staff relations during the war, and internationaly relations postwar. But it seems likely that the British refusal to even consider such nonsense was taken by Marshall and Stimson as a sample of the British being duplicitous about “examining planning options”.

The British fixed on a “compromise” to pretend that a “second front” could be possible. North Africa, could be conquered without prohibitive losses. It was not ideal, and in practical terms not even very useful. But it might satisfy the Americans and the Russians. Nothing else could.

Marshall in particular spent the rest of the war believing that when the British assessment clearly demonstrated that action in Europe was impractical and impossible, they had just been prevaricating to get what they always intended: operations in the Med. In some ways he was correct. The British had done the studies on France despite thinking that it was unlikely they would be practical, and were proved right. Marshall and Eisenhower had just deluded themselves into thinking an invasion might be practical, and could not accept that there was not a shred of evidence in favour of their delusion.

Nigel Davies, “The ‘Invasion of France in 1943’ lunacy”, rethinking history, 2021-06-21.