DDay becomes a fantasy without the USSR tying down 82% of the axis forces on the eastern front.
Consequences of the collapse of the Soviet Union for the Pacific War
- Thread starter Juan de Mariana
- Start date
DDay becomes a fantasy without the USSR tying down 82% of the axis forces on the eastern front.
Because the vast majority of resources were taken when fighting the Soviets (80% of Germans forces in the early stages and never went under 60% in the entire war), the only significant loss of the Germans to the WAllies before D-Day was in North Africa in 1943, without having to fight the Soviets a lot of resources are free to be used elsewhere. Imagine if the Germans could use most of their troops against Operation Overlord, there is no way it can work and that's not talking about the fact that a lot more resources could be used on the air and navy preventing any D-day at all.
No, the Lend Lease was not a big price to pay for the US and UK in exchange for a stronger USSR which did most of the fighting trough the entire war, the UK will suffer more since now they're the only ones fighting the Axis in Europe until the submarine problem in the Atlantic is solved.
Because the WAllies were very casualty averse. As horrible as the Nazis were they were not capable of invading the UK or the US, so without the Soviets to the pay the millions in lives to topple the third reich the WAllies people would not have accepted sacrificing millions of their young population to secure a defeat against the Nazis against a country that did not pose a direct existential threat against them. This was why they were willing to give the Soviets everything they asked for in lend lease regardless of future consequences because if the Soviets collapsed during WW2, that frees up 6 million axis soldiers for the western front.
It’s a really interesting phenomenon. Between the years of 1922-1937 and 1946-1991 the Soviet Union collapsing would be seen as one of the most positive things to happen for freedom and prosperity in the world.
The Soviet Union collapsing between the years of 1938-1945 would be seen as probably the most horrific tragedy of the 20th century And everything must be done to ensure that it does not happen.
We’ve had countless lengthy threads about this topic (seven of which are linked here in an old post I made) that I think everyone should read. Assuming the USSR gets defeated I think there’s a 40% chance at least that the WAllies decide the blood price is too much to pay to defeat the Greater Germanic Reich and an uneasy cold war develops like AANW. Peace or no peace I think in this scenario the WAllies would decide to blockade and bomb Japan into submission instead of an actual invasion. Japan gets turned into Dante’s Inferno depending on how soon the leadership see reason.
I agree the WAllies were casualty averse, and D-Day is unfeasible in 1944. However, much depends on the 'how' of the Soviet defeat. The Nazis are still likely to be expending considerable (if fewer) resources in the East.
But... I think saying the Nazis do not pose an existential threat to Britain is a conclusion taken with the benefit of hindsight, and I am not talking about an invasion.
Without D-Day, there is something of a stalemate. A WAllies Bomber Offensive is much more costly. An extended Cold War means the Nazis bed in. At some point, if they realise atomic weapons are feasible, they are going to want them too. Or maybe they go down the biological route. They are, after all, batsh!t crazy.
So, potentially at some point the WAllies do indeed have to take the plunge and invade Europe. Maybe with atomic weapons clearing the path. It will be horrific, but betting the Nazi regime implodes before doing something else horrific and stupid is rather risky.
The "Atlantic Wall" was where the Heer sent formations to reconstitute after getting mauled in the East/West Africa and "static" divisions (with a high percentage of Ostlegionen and Hiwi personnel). The Wall, and France in general, was far less well garrisoned than any of the Eastern Front Army Groups especially in armored formations and in bombers. By mid 1944 the CBO had drawn much of the Luftwaffe single engine strength and night fighter strength back into Germany in an increasingly futile efforts to defend Inner Germany..
Somewhere in the area o 80% of the Heer was deployed on the Eastern Front. If even 350,000 of those troops had been deployed to the Atlantic Wall/Western France the WAllies would have never even attempted to land without literal years of battlefield prep.
So in OTL, part of the reason for the rapid collapse in Manchuria in 1945 was that the Japanese had already been stripping their formations there of manpower and more importantly, mobile equipment, for service in China and the Pacific. So I think we would see a much earlier transfer of assets from NE Asia to the Pacific. But 1944 onwards saw the shipping lanes come under American Submarine attack and the Japanese started losing supply and troop convoys, so it would have to be earlier.
I don't necessarily think the Western Allies were that casualty averse. The Americans generally preferred firepower and close air support as the breakthrough element in contested advances over large scale infantry maneuver, but that was because they had this as an option. Commonwealth Armies certainly were not casualty averse. The Free French in 1944 were a bit more casualty averse in that they had a small cadre of forces that they could not afford to lose for the planned wave of mobilization in 1945 after liberation, but this was a small part of the overall Allied effort.
The US Army did not lose a single Division level element in the European theatre of war - the closest was the 106th Division, which saw about half its strength overrun at the start of the Ardennes Offensive, but even that unit didn't require complete reconstitution. This was largely because of how the fortunes of war went for the US in 1944, not because of an averse approach to casualties. When Allied forces were capable of offensive action, they engaged in it and took losses accordingly.
They similarly engaged in the same tactical ineptitude at Monte Cassino and Hurtgen Forest as the Soviets showed as First Jassy-Kishinev, Rzhev, and Narva, so I don't think its necessarily a case of national military cultures or anything like that.
I would argue that the Soviets often were wasteful with manpower - not in the sense of memes about human wave assaults, which are false, but in the way that the echelon style of attack ended up working in terms of how efficiently reserve units were deployed to points of breakthrough, the performance of its corps and army level commanders in ascertaining accurate information and relaying it faithfully up the chain of command (a huge problem), the level of training for infantrymen (a problem that probably could not be avoided early war, but was unacceptably an even bigger problem late war), and at the end of the war, in the mix of tanks, mechanized vehicles, and infantry in their mobile formations - they took extreme tank losses because their formations were too tank heavy and vulnerable to PAKfront in depth tactics, hunter-killer teams, and German defensive armor tactics, and this was not necessary had they had adequate support ratios.
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I disagree. With the Germans somehow successfully defeating the Soviets, the WAllies would be more likely to consider that actually fighting the Germans on the Continent is impractical, at least in the short term.
So for at least the next few years at least the ETO would likely be limited to simply containing the Germans on the Continent by maintaining a naval blockade and securing the sea lanes from u-boat attacks.
The main focus of the war will move to dealing with the one Axis member the Allies could defeat: Japan.
And on that note, Jiang's pre-1937 connections to Nazi Germany didn't help in that regard.
Depending on if Jiang pisses off the Americans even further, there's a very small chance the Americans might decide not to hand Formosa over to them either. Very unlikely, but not impossible, as ultimately outside of the Home Islands (all of which were non-negotiably part of any Japanese nation) whatever islands the Japanese get to keep would be decided by Allied consensus. If Jiang burns all his bridges with the West, I can see an outcome where Formosa goes the way of Okinawa, i.e. American-administrated territory for a few decades, before being turned over to either Japan or China so long as the USA gets to keep stationing troops on the island. Since there's no way the Chinese whether KMT or CCP would allow that, well, Formosa could stay Japanese into the 21st Century.
Again, very unlikely, but not impossible, considering how Truman was prepared to let Mao chase Jiang out of the mainland IOTL. If Mao gets screwed over by the loss of Soviet support, and the KMT secures of Manchuria and its industries first, and destroys its relations with the Americans, I can see Truman (diplomatically) telling Jiang to f*ck off with regard to Formosa.
While these are points worth considering, I believe that these are somewhat overstated.
The strength of the German army on the eastern front at the close of 1941 was in the region of 3.5m men. Assuming Moscow is taken by Christmas 1941, Stalin, (or, more likely his successor), negotiates the surrender with Nazi Germany and a border is drawn roughly halfway between Moscow and Kazan, (roughly half of European Russia), this, along with Poland and the Baltic states, and the pre-war acquisitions, (Czechoslovakia for example), gives an occupation zone of roughly 1,270,000 square miles that needs to be secured in the east.* That's a lot of ground.
By Hayden120 - "Utopia: The 'Greater Germanic Reich of the German Nation'". Institut für Zeitgeschichte. München - Berlin. 1999., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=18153420
Out of 3.5m men, I don't think it's unreasonable to assume that around 1.5m of those would be needed, (minimum), to secure the new 3500km border which now stretches from Mezen in Northern Russia, down through to the Georgian border. This was the sort of area the Greater German Reich proposed to settle.
Around 500,000 would be required to secure the conquered territory, clear the villages, partisans, transport the victims to the concentration camps, or into the slave labour camps, or just murder them. It was expected that should this have gone ahead, estimated deaths would have been around 60m. Carrying this out requires a lot of man power and a lot of time.
We're back now to around 1.5m soldiers being available for the western front. However, I don't believe Germany could have afforded to keep the level of military spending up to have an additional 1.5m men sat around enjoying the French countryside. If I remember correctly there were about 175,000 men on the west wall, most of them being Hiwis, so they'll need replacing. Still leaves around 1.4m, give or take, kicking their heels. However, Nazi ideology being what it is, will want German women back in the homes and having children ASAP, not in the factories wherever possible. In 1939 there were around 2.7m women in factories, some of those can be replaced with slave labour, (cheap), but they would still need supervising, that will swallow a few hundred thousand, between guards, service staff, escorts, managers etc. There will be men discharged, those hitting the upper limits of conscription age for example, those that had been wounded and recovered, those with "interesting" disciplinary records. These men would go into the reserves. You're probably left with a million extra men. Some of those could be sent to North Africa. Additional troops to replace the use of local militias in the Balkans and Greece too, and all of a sudden, that million extra men start to evaporate until they're all gone.
The defeat of Russia also has a few other changes. The arguments by the Wehrmacht that they needed Steel for tanks to use in Russia has evaporated, and so the Kriegsmarine gets that steel for U boats, or better, (from the Allied POV), surface ships. That's a lot of tanks not being built.
On the shipping front: if the Kriegsmarine get more U-boats, with the breaking of the Enigma codes, potentially the capture of more machines, it could mean the second Happy Time last longer, and more allied ships are sunk, however I'm not convinced that it will be much more given that the British and Americans are no longer running convoys to Russia, I suspect those losses are likely to balance out on the allied side, with a similar proportion of the total U-boat fleet lost to OTL.
Thinking of tanks, the types of tank is also impacted. Without having to face the T-34 or the KV1 in any significant numbers, there's a good chance that the Tiger as we know it never exists, and the Panther, if that exists, may not have the sloped armour inspired by the T-34. Without the need for heavier tanks like the Tiger, or the heavier self propelled anti tank guns, I would expect the PzII, PzIII and Pz IV design arc to continue, and the PzV could end up being a version of the Panther but with the flat fronted, hardened steel upper glacis.
Another change: Combat experience. The Wehrmacht won't have nearly as much as they did in OTL unless it comes from the Afrika Korps, or, it will be a different kind of fighting entirely - anti partisan fighting. The OTL lessons of the Eastern Front won't be learned, the veteran units rotating out of Russia for rest and recuperation in France, won't be as hard bitten as OTL. They'll be as effective as OTL against the various resistance groups, but less so against an organised army with artillery.
Also, the Luftwaffe will have far fewer aces, and where older and more obsolete airframes, (the JU-87 or BF109E-F), will survive than OTL. So while they have numbers, they will be lacking some of the quality of OTL. I don't see them having much effect on the European bombing campaigns unless it forces the USAAF to switch to night raids earlier or bring over more P-51s.
Without the inexorable OTL march of the Soviet Union from the east, what effect will that have on the V weapons or the speed at which aircraft like the ME-262 or ME-163 Komet happen?
I suspect this may also butterfly the STG43/44. Without the experience and losses of the eastern front, the need for an intermediate cartridge also goes. or at least it goes into the background. There's a good chance that the Panzerfaust goes the same way.
On the Allied side, America is still in the war, so I would expect the bombing campaign to continue although the targets that were selected purely to assist the Soviets are likely to be left until they assist the Western Allies. Given the additional space, this could see German war industry take a dip as it's moved eastwards, into Poland for example to save it from USAAF and RAF bombing raids.
This could see the B-29 or similar being brought in earlier. Aircraft with a longer range and the ability to fly at higher altitudes could become a priority. Or potentially, a V2 analogue being developed by the Anglo American arms industries.
The amount of American equipment that was sent to Russia now doesn't go, part of that could end up in Britain instead, although I don't think there was physically enough room for all of it in Britain.
The P-39 Cobra becomes an interesting footnote, nothing more.
FUSAG maybe becomes real.
Things I don't see changing:
Hitler being, well, Hitler and interfering in military matters. This was probably the best advantage the Allies had.
The Western Wall being built as OTL, possibly more slowly than originally, but it will still be built, and probably with more slave labour than "guest" labour.
US Production levels. They won't be dropping, although they may rise slightly.
North African campaign. North Africa is a side show for the Nazis. It has no tangible benefit for Germany to throw more resources into it.
Allied Air Supremacy over France by 1944.
How do I see things progressing?
The Dieppe raid takes place as OTL, the same lessons are learned.
Without the pressure from the Soviets to "do something" in 1943, does the invasion of Italy happen? If it does, are additional German troops sent to defend Italy? Any German troops sent to Italy can't also defend France.
Case Anton - the German occupation of Southern France, this time with more than just 7th Army. Any additional troops sent there can't defend Normandy.
If an invasion of Europe is deemed a possibility, the most likely route, and the one Hitler was convinced was the only real one, will be via Calais, so additional troops, possibly called back to the colours after a year or so demobbed, would likely be sent to Calais instead - not defending Normandy.
While the Germans would have additional tanks, they would still be heavily outnumbered by Shermans of all stripes. The only real limit on the number of tanks the US army could field would be finding crews for them all. plus, more German tanks means more targets for the Anglo American Jabos.
Where additional troops gather, they become a target for aerial bombing.
I think D Day still happens in June 1944. It will still be a success. Any additional soldiers or armour are likely to be sent to Calais first. Given that the German army is still predominantly horse drawn, I don't believe that they will be able to move, (once Hitler finally agrees to release them), fast enough to prevent the allies form landing successfully and establishing themselves. While the Germans will be able to bring greater numbers to bear against the Western Allies, they won't be as effective as OTL, More dead, more injured and more taken as POWs. The Western Allies haven't really lost anything. The majority of their actions haven't been affected by the Russian capitulation.
The casualties would be significant, but given the Americans alone, were prepared to accept over a million casualties to invade Japan, I don't think they would baulk at it to end the war in Europe. As for timings, I think May 1945 to reach Berlin is still feasible under these circumstances. especially with the Western Allies far greater mobility than the Germans. And hopefully, along the way Market Garden is butterflied out of existence.
Just a thought.
*At this point we don't need to consider the roughly 210,000 square miles of occupied western Europe.
The US was not ready to take a million casualties to invade Japan, which is why they didn't IOTL and preferred sending nukes, asking the Soviets to invade Manchuria and watching Japan starve until surrender.
Anyways the Germans might have less troops at the beginning but in the unprobeable case where D-Day still succeeds, they will face the full might of the German war machine, the Germans for years survived while fighting the Soviets and the Western Allies, there is no way that Nazi Germany plays their cards so wrong that it loses at this point.
With extra resources what guarantees you that they still beat the submarines (IOTL beat in 1943)? That they still manage to defeat the Luwtwaffe without extra fronts to care about (to fight resistance groups you need much less air support) and with more resources? What guarantees you that there are the same numbers of troops on the West wall?
With more resources available on the Western Front, there is no way the Germans are collapsing in any similar timeframe of OTL, even in its final days the Reich managed to carry out the Bulge seriously putting in difficulties the US.
And what about the troops that were fighting in Poland, Romania, Hungary etc. ? The Germans are going to re-mobilize if they are in difficulty and any advance on Berlin will be done at the cost of millions of men which were conveniently spent by the USSR IOTL.
I would agree the Germans would have the upper hand in a 1944 invasion scenario where they could do larger scale armored counterattacks and the Atlantic Wall was manned by more seasoned and well equipped forces.
But a serious question here is the air war. Without the East they'd be in a better position, but would they be able to take back control of the skies in the west? I'm skeptical, at least by the time the US joins the war. And that opens up a lot of issues - let's say the Allies cannot make headway - DDay fails and requires evacuation, the Allies take Sicily but cannot move up into Italy - but then they are able to nuke the Germans in 1945 and proceed to destroy several cities. Would there be a negotiated peace?
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I believe this is incorrect. The plans for operation Coronet and Operation Downfall remained in place as late as August 1945. As for Casualties, all the briefings given, officially and unofficially stated that the expected casualties were between 500,000 and 1,000,000. To the extent, that by the end of 1945, over 500,000 purple heart medals had been stockpiled, of which, there are still around 65,000 remaining, (quoted as 120,000 as of 2003, and a little over 50,000 US casualties since then). I consider the arguments that the American military were "casualty averse" during WWII, or that they were not prepared to take massive casualties to be largely without merit.
As above, Downfall and Coronet were still in the plans until the Japanese Surrendered. Indeed, later incarnations of Coronet and Downfall from after the attacks of Hiroshima and Nagasaki, discussed the use of atomic weapons in the tactical role.
The Soviets joining the war against Japan had been agreed in 1943, this decision did not have an effect on American plans to invade Japan.
The successful invasion of Manchuria and the surrender of the Kwantung army was a factor in the Japanese decision to surrender, however I have found no record that the Americans directly requested this to force the Japanese to surrender. I would welcome any reputable sources contradicting this.
As for the "starve until surrender" option, this was favoured by the US Navy, particularly Admirals Nimitz and King. In the event that the Japanese had not surrendered around August/September time, it is still entirely feasible that the invasion would have gone ahead as planned.
This bears some deeper explanation. My supposition of Overlord succeeding is based on the Western Allied not making any changes to OTL plans.
Significant Allied efforts went into the misdirection of German military planning, directing German attention away from the proposed landing sites. These efforts utilised Hitler's cognitive bias in favour of a landing at Calais, as such, OTL and ITTL, the vast majority of German preparation was directed there.
OTL, the orders to release the Panzer reserve were not received until 1600hrs, 14 hours after the invasion started. Assuming an infantry reserve is the same and has to travel from Calais, by horse or by foot, it will take them roughly 3 days in optimal conditions to march the 300km. It would likely take the same to move by train, however given Allied Air Supremacy, (at worst, Allied Air Superiority), this would have been a risky manoeuvre, due to roving allied fighter bombers.
Even once this is complete, the possibility of moving within 10 miles of the beachheads is not a simple proposition guns of USS Texas, USS Arkansas and USS Nevada to the west, and HMS Warspite and HMS Ramilies to the east. This doesn't take into account the various cruisers, destroyers and monitors also on station to provide fire support.
There is very little the Germans can do, through their own leadership, and OTL allied preparations to prevent D Day from being successful overall.
This is hard for me to say as an Englishman, but Germany lost all their winning cards when Hitler declared war on the USA on December 8th 1941. America alone was capable of out producing, out equipping and outfighting the Germans. Add the not insignificant contribution of the rest of the allies into this and the defeat of Germany is inevitable. The only real question is the manner of that defeat.
While in my previous post I suggested that the defeat of Russia means that the Germans would redirect steel production from tanks to U Boats. There would be a minimum 10 month delay from that point to the first of these U Boats going to sea due to the time taken to build a U Boat. This assumes that German shipbuilders have the slip capacity to actually build the U Boats. Assume that they don't. It would be around 12 months for a new slip way to be built, then a further 10 months for the first of the additional U Boats to head to sea even if they were sent, still with wet paint and wet crews into the Atlantic. Just under 2 years. December 41 to December 43 before they make it to sea.
In this time, assuming no other delays due to design changes, the Western Allies are building Corvettes and Destroyers, improving their ASDIC capabilities, still reading German messages as fast as the Germans can send them, (that is OTL), If there is a third surge of U Boats in 1944, then there is a third surge of German U Boats visiting the bottom of the Atlantic, if for no other reason than USN and RN ASW techniques had continued to improve. The biggest bar to further improvement in ASW tactics, techniques and strategies OTL was a lack of targets to practice on.
Neither the British nor USAAF were short of pilots or machines. One issue the Luftwaffe may face is that while they have more resources and less to worry about from the Eastern Front, they also lack the experience of fighting the VVS meaning 1) there will be far fewer aces and 2) they will be less prepared to face the far better trained USAAF or RAF pilots.
Probably the biggest change will be more fighters in the west, with ground attack aircraft, such as the JU-87, JU-88 or HS129 being used to support anti partisan operations in the east. The JU-87 and HS129 took significant losses in combat zones where the Luftwaffe did not hold at least local air superiority.
one of the bigger issues I think the Luftwaffe face in this scenario isn't the allied airforces, but their own leaders. Take the ME-262 as an example. The development was delayed because it had to switch from being a bomber killer to being a dive bomber on Hitler's orders. Hitler hasn't gone, and if anything, with the defeat of the Soviet Union, he will be even more convinced of his own "genius". And what of Goering? A lot of interesting decisions came from the drug addled muppet, (who had, without the drugs, according to American testing before the Nuremburg trials, the highest IQ of the surviving Nazi leadership). What get's built? With more resources, (which can only be spent once), What do you build? I believe that Goering would have pushed for more Ar-234s and more ME-262s. These had teething issues so I don't see more going into service earlier than in OTL, although they can probably manage more than 25 hours engine life. I suspect the lure of jam tomorrow at the expense of bread today would see the ME-262 pursued at the expense of many more ME-109Gs or FW-190 Doras. Unfortunately, I don't see the Luftwaffe, based on OTL behaviours of the Nazi leadership, having the intellectual capacity to make better decisions than OTL.
I would expect more troops on the west wall, something I posited in my previous post. I don't believe that given where they would likely be deployed, that they would make much difference to the success or failure of Overlord.
Having the resources and using them effectively are not the same thing. Unless there is a change in the leadership, then all it really means is that once the allies are out of the Normandy beachheads, the collapses are likely to be more spectacular.
Indeed, the German's manage to cause problems for the Americans in the Ardennes, but at best they would manage a tactical victory, not a strategic one, the end result is that the fuel and men used in that offensive are used and cannot be used again elsewhere.
The troops you mentioned above, that fought through Poland in 1941 are already accounted for. The ones that fought through Romania, Hungary back towards Germany in 44-45 et al are the ones, with replacements that fought their way to Moscow so are also mostly accounted for already. See below.
I agree. They will. But at what point? Bear in mind it will take a lot of time to remobilise the, (lets say), 1,000,000 men demobilised after the Soviet collapse. First you have to round them up, get them to barracks, equip them, train them, feed them and transport them. You're looking at what, maybe 60,000 a month assuming no difficulties, so around a year to bring them all back, even with reduced training time for the veterans. The new recruits would still need their full training. At the beginning of the war, this took 6 months. Even if you reduce this to 3 months, that still delays getting additional soldiers to the front. So when do you start calling them up? Say June 1944. that means you have 360,000 additional soldiers by Christmas. Maybe 450,000 if you include new recruits at a push. In 6 months. OTL the US alone was sending 250,000 per month in 1944. They are sending three times as many soldiers as the Germans can recruit, train and send. From the opposite side of the Atlantic.
This is a false equivalence and assumes the western allies will lose as many men as the Russians did, despite fighting in very different terrain, very different weather and with very different strategies. It's also worth noting that the majority of the Soviet losses, (a little over half), took place in the first third of the conflict with Germany while they were on the defensive, with the other half of the casualties spread over the remaining 2/3 of the war when they were on the attack. I suspect that similar, political issues that hampered STAVKA in the defence of the Soviet Union, contributing to the significant casualties they suffered are likely to face the Germans too ITTL.
I have no doubt Western Allied casualties would be higher than OTL, even if they increased by 50%, it is still under a million.
The preceding suppositions on my part are that there are no significant changes to Western Allied plans for Overlord in the light of the Soviet collapse of 1941/42.
What happens if they do alter their preparations?
Air campaigns
Instead of bouncing the rubble of Berlin, or Hamburg or a myriad of other cities, expect more attention to the Railway campaign, especially in France. This removes the German ability to move forces, especially heavy items such as tanks, artillery and supplies quickly to where it's needed. This forces German to use the roads. This drains German fuel reserves. All the petrol used to move trucks can't be used to move tanks. If you use it to move tanks, you burn a lot more fuel and, you reduce the availability of the panzers as more of them are out of action for maintenance issues, which means you're waiting on trucks that have to wait on fuel which may or may not arrive.
To compound matters, bomber sorties used in Italy OTL, could be redirected to Ploesti to keep hitting the refineries. Of course, defending those refineries means either moving additional aircraft and/or addition AAA guns which then can't be used in the AT role in France or to defend USAAF/RAF targets in Germany.
On a tactical level, reconnaissance flights OTL mapped pretty much every German gun and emplacement in Normandy. This is unlikely to change. Any additional troop build up, especially within range of the Naval guns, is likely to be added to the list of targets to be hit or bombed.
Likewise, for the troops in Calais and in the region of Dunkirk, (where Rommel expected the landing to take place), will be spotted and targeted. Part of the OTL allied deception plans for D Day meant for every sortie over Normandy, two were flown over Calais to reinforce the impression that Calais was the target. In the event that additional Germany military units are sent there, (and the French Resistance was very good at reporting these movements back), it's likely to alter to three visits to Calais and one to Normandy, with tactical bombers such as Mitchells, Marauders and Mosquitoes making the attacks with RAF fighter support. More troops in an area means more targets and more casualties. This will erode the supposed numerical advantage of the German army significantly.
Additionally, instead of using Tall Boys and Grand Slams on U Boat Pens, make a show of using a number against the West Wall fortifications around Calais and Dunkirk, (and the odd one on the Normandy defences), until June 5th 1944 when you use a sortie on each of the proposed landing beaches. The damage of the bombs isn't what they achieve above the ground, but the effect of the penetration in destroying the defences from underneath, helping to breach the defences before the first man has landed on the beaches.
Naval Preparation
I believe that this would see, as part of the planning effort, increased heavy naval presence in the English channel, meaning more guns hitting inland targets until the allies have advanced out of range of the Naval fire support, and their own artillery is now supporting them. It's likely HMS Malaya, HMS king George V and HMS Duke of York joins the deployment, this would increase the naval support available.
Land Forces Preparation
400,000 jeeps and trucks, 7000 tanks, (4100 of those were M4 Shermans), 11,000 combat aircraft were sent by the Americans, 4,000 trucks, 5000 tanks, 7000 combat aircraft, 2500 Lloyd Mortar/Bren carriers and over 5000 anti tank guns sent by the British to the Soviet Union as part of lease/lend. These are available for the Western Allies instead. the struggle is finding the manpower to run them all.
What I believe would happen is that the quantity of what was available, especially for transporting men, equipment and supplies would greatly increase leading to the Western Allies being mechanised to a degree the Wehrmacht could only fantasise about. This would mean that where opportunities for encirclement present themselves, for example around Falaise, it would be easier for the Allies to achieve the encirclement, that can then be bypassed and reduced by the follow on forces as per OTL.
This would impact the selected tactics and could possibly facilitate the sort of mobile warfare practices, especially by the British in North Africa, giving the SAS and their former LRDG members an opportunity to adapt the warfare they had been practicing for a few years to the countryside of France.
I would expect the British, Americans and Canadians would increase their man power in the year preceding Overlord with the possibility that Australia could be persuaded to contribute troops too.
In these suppositions, both the Nazis and the Western Allies are better off, however, both quantity and quality favour the Allies. For these reasons, and the reasons above, I believe that not only to the Western Allies win WWII in roughly the same timeframe as OTL, they do so without the use of Atomic weapons in Europe.
While I don't agree with the scenario you've given, if we were to follow it, I think your proposed outcome is exceptionally plausible.
Coulsdon Eagle
Monthly Donor
I have to disagree. OTL Monty in '44 was well aware that Britain's manpower resources were running low, which is one reason he tried an awful lot of expensive battles using armour rather than infantry. AA regiments were being disbanded and sent to France as undertrained infantrymen. Also Britain's top military commanders had all come through the Great War, the first war in centuries that had involved major loss of British & Imperial soldiers, sailors & airmen and the cost to the nation of those suffering life-changing wounds; I struggle to think of any British commander outside special forces who were not casualty averse in a way that the Russians, Japanese & Germans usually were.