Had Germany been aware of D-Day could they have repulsed it? (Mexico, 1930s)

[John-UK]

The primitive decoding machines in England that deciphered German communications were the world's first 100% electronic computers.

Another allied advantage was the total control of the seas around France.

[msgsing]

Originally Posted by John-UK

The primitive decoding machines in England that deciphered German communications were the world's first 100% electronic computers.

Another allied advantage was the total control of the seas around France.

Yes your right. And it was a closely held secret right up to the 1970’s when ULTRA was finally disclosed to the public. You have to wonder about the skill level of some of our highly rated allied military leaders when they had such a huge intelligence bonanza in their hands and knew what the Germans were up to everywhere and everyday.

[CrazyDonkey]

The broader question is whether Germany could have withstood invasion from the west if they hadn't invaded Russia. It certainly would have been much more difficult, and costly, even with the diversion of some forces to counter an eventual threat from the east not being eliminated. The thesis behind Operation Barbarossa was that the Soviets were inferior pushovers who could easily be knocked out of the war.

[2x3x29x41]

Originally Posted by North Beach Person

Maybe. But if, since we're playing what if, the Germans had been able to throw back the invasion the whole strategy of the Western Allies would have had to change. The failure could have pushed Stalin to seek a negotiated ceasefire/peace, something that Roosevelt and especially Churchill were very concerned about. In fact, the deal was that once the beachhead in France was established then the USSR was to launch an attack on the Eastern Front within a short period of time (Churchill was thinking days) which didn't happen until June 22.

There was serious concern almost until the Fall of Berlin that Stalin would seek a negotiated peace with Hitler. Whether that was really a legitimate fear is another question. With Stalin nobody ever really knew.

I don't think a failure of Overlord would have cancelled the Soviet offensive (Operation Bagration). The timetable was set by the Soviets in April - and the western Allies weren't telling them precisely when D-Day was going to take place - and in any case, even a failed invasion would have been a major distraction for Germany. As it was, Hitler was convinced by Allied deception that there would be a landing at the Pas de Calais in July, to the extent that for weeks reserves were held in the area for the 'main force' that would follow the Normandy 'diversion'. Besides, the Soviets had clearly gained the initiative by June. Cynical Stalin might well have seen the upside that he'd get more territory, albeit at a price of more troops (which he'd have happily paid) as a result.

Originally Posted by North Beach Person

Remember that 1944 was an election in the US. Would Roosevelt have survived a D-Day debacle? He was already showing signs of what would be his terminal illness.

Would Churchill have faced a no confidence vote in Parliament? He really didn't want a landing in France anyway, he focused a lot on the Balkans and Russia closing in on SE Europe.

These are excellent points. Often the political aspects of war are ignored in favor of simply comparing military capabilities, but history is strewn with lesser forces that won wars because domestic politics forced the stronger powers to throw in the towel.

Originally Posted by msgsing

Realistically I wonder if Truman would have ever used the atomic bomb on Germany. We had hundreds of thousands of German Americans living in the United States. Would it have been a post war political liability especially for a President who intended to make a run for a full term in the White House. In that era America was decidedly Eurocentric whereas the Japanese were just Asians.

The Manhattan Project was begun in order to beat Germany to the bomb.

This tends to be obscured by history, because by the time it looked as though a deployable bomb was feasible and going to be available in the near future, Germany was on its last legs. So most of the serious planning focused on Japan. However, had Overlord failed then the timeline for Germany's defeat would have been stretched out considerably.

During the Battle of the Bulge, a disturbed FDR had inquired as to the possibility of using atomic weapons, when available, against Germany (this per General Leslie Groves, who ran the Manhattan Project). So it was clearly a consideration, and it seems unlikely that a President Truman would have been more averse to this eventuality, especially considering that lacking a foothold on the continent entirely would have left the Allies in a far less advantageous position than in the darkest hours of the Battle of the Bulge.

That said, there were some limitations to the possibility:

*Japanese building materials made their buildings, especially residential, far more vulnerable to both the blast wave and incendiary effects of nuclear weapons.
*Japanese air defenses were far less formidable than those of Germany. The Hiroshima mission consisted of six B-29s - the Enola Gay and five aircraft devoted to weather reconnaissance and observing/measuring the effects of the blast. That would not have sufficed over Germany, where the Luftwaffe had been significantly reduced but was still rising to meet bombing raids. And the Germans made it a point that when new equipment appeared over the skies, everything was done to down it so that intelligence could be had. B-29s over Europe would have garnered a lot of attention (the U.S. had nothing else that could carry atomic weapons). The U.S. would have been very wary of the possibility of a atomic-laden aircraft being lost, its payload possibly recovered.
*To that end, American planners were worried about a 'dud' that survived its drop to some degree. Though the German atomic bomb project was far off the rails in 1945, the U.S. knew that Germany was much further down the road of development than Japan, and that recovering a bomb that failed to detonate might help it in ways that Japan could not have benefitted.

Presumably, with the western front secure, the USSR's advance slows. But it probably doesn't stop. Let's say the summer of 1945 rolls around. The western Allies still aren't on the continent. The Red Army is in Poland and slowly moving west. Italy has mostly fallen, but the Alps loom as an impenetrable barrier. Maybe some form of Dragoon has come off, but France mostly still languishes under the Nazi boot. Does President Truman order a target list of German cities drawn up?

I think so.

Originally Posted by CrazyDonkey

The broader question is whether Germany could have withstood invasion from the west if they hadn't invaded Russia. It certainly would have been much more difficult, and costly, even with the diversion of some forces to counter an eventual threat from the east not being eliminated. The thesis behind Operation Barbarossa was that the Soviets were inferior pushovers who could easily be knocked out of the war.

Well, it's hard to imagine any Germany leader other than Hitler having the audacity to try and take down France and roll up the rest of western Europe. There was a gret deal of trepidation among German generals and other leadership that the plans of 1940 were insane and doomed to failure. It's also hard to imagine that Hitler never invades the USSR, because expanding to the east was the entire point of his political agenda and his military adventures, the western invasion merely being undertaken to secure his flank so that he could move east. And by 1943 at the latest, Stalin's furious rearmament and the Red Army's reorganization would have been largely complete, so by 1944 there's a good possibility that Stalin decides to strike before he can be struck.

[M3 Mitch]

Getting back to a detail about sea mines, I am not aware of any WWII era mines that could be de-activated or re-activated remotely. There were some clever designs, anti-sweeping measures, but as far as I know they simply remained armed as long as the firing mechanism and explosive remained viable, and that could be several years. Once laid, they simply blew up whatever triggered them, by contact, acoustics, or magnetic triggers. The contact mines did not have any "live" electronics until triggered, so would remain viable for a long damn time.



https://en.wikipedia.org/wiki/Naval_mine


If I am wrong, set me straight.

[John-UK]

Originally Posted by msgsing

Yes your right. And it was a closely held secret right up to the 1970’s when ULTRA was finally disclosed to the public. You have to wonder about the skill level of some of our highly rated allied military leaders when they had such a huge intelligence bonanza in their hands and knew what the Germans were up to everywhere and everyday.

Sometimes it never mattered if the enemy knew what you were doing, as it was self evident.

[CrazyDonkey]

Originally Posted by 2x3x29x41

It's also hard to imagine that Hitler never invades the USSR, because expanding to the east was the entire point of his political agenda and his military adventures, the western invasion merely being undertaken to secure his flank so that he could move east. And by 1943 at the latest, Stalin's furious rearmament and the Red Army's reorganization would have been largely complete, so by 1944 there's a good possibility that Stalin decides to strike before he can be struck.

Except Hitler's decision to invade Russia was predicated on his belief that the Soviets would be easy pickings, which was delusional. If he'd come to his senses, recognizing what he was risking, would he have still invaded? It was clearly the most direct cause of his and Germany's defeat and the main reason they were unable to defend the Atlantic Wall.

Stalin was clearly shocked when Hitler invaded. He was content to watch the "capitalist" powers fight it out, weakening each other, while the Soviets sat on the sidelines and built up their strength. He might have even continued to supply the German's with oil and other supplies, since a stalemate in the West was in his best long-term self-interest.

[John-UK]

Hitler had a long term ambition to seize eastern Europe creating a United States of Europe. In May/June 1940 there was no plan to invade the USSR.

"Roosevelt's announcement in May 1940 that he wanted to see American industry turning out at least 3,000 aircraft per month and reaching a final production level of 50,000 sent shock waves through the Reich Air Ministry."
- Wages of Destruction by Adam Tooze

"Britain inherited France's orders in the United States. Combined with the contracts Britain itself had placed since the start of the war, London by the end of lune 1940 was expecting delivery from the United States of no less than 10,800 aircraft and 13,000 aero-engines over the next eighteen months. This was in addition to Britain's own production of 15,000 military aircraft. At the same time, the British Ministry of Aircraft Production was negotiating with the Americans to order many thousands more. By way of comparison, total German aircraft production in 1940 came to only 10,826 aircraft and in 1941 it expanded to only 12,000"
- Wages of Destruction by Adam Tooze

Britain would have 26,000 new planes to Germany's 11,000. A massive difference.

"The floodgates in Luftwaffe planning finally opened in the summer of 1941 with the completion of the army's Barbarossa programme and the long-awaited decision to shift priority to the air war. In June 1941 the Air Ministry proposed a doubling of output to 20,000 aircraft per year over the following three years."
- Wages of Destruction by Adam Tooze

"aircraft production takes time - at least six months from raw material to finished aircraft. It is hardly surprising, therefore, that the large increase in the Luftwaffe workforce in 1941 did not immediately result in a surge in production."
- Wages of Destruction by Adam Tooze

The Germans needed the resources of the east to fight the coming air war.

"Meanwhile, the rest of the German military-industrial complex began to gird itself for the aerial confrontation with Britain and America."
- Wages of Destruction by Adam Tooze

[Potential_Landlord]

It's really crazy how Hitler waged war with such limited resources compared to the Western Powers, let alone in combination with the USSR. The German general staff and civilian leaders pointed this out to Hitler before the war, yet his decision to gamble on war was largely based on the Munich Conference 1938 negotiations with the French PM Daladier and British PM Chamberlain in my opinion. He always called them "worms" and how they would crumble if he applied any little pressure on them. He extrapolated that their armies and peoples were defeatist. Hitler was right about France, but not England under Churchill. This is a most important lesson for all of us. World Peace requires credible deterrence of rogue regional leaders. Today, the US is largely required to provide this deterrence. A recent example is how the Iranian navy stopped their regular harrassing of US vessels in the Persian Gulf after Trump's election. Other than Obama, Trump is unhinged enough in the eyes of the Iranian leadership so they do not risk a confrontation. They judged differently about Obama. If Daladier and Chamberlain had been equally inhinged, menacing and forceful to Hitler about Czecho-Slovakia and Poland, history may have been different.

[John-UK]

"It has sometimes been said that it was the last-ditch effort at conciliation undertaken by Chamberlain which undermined the resolve of this group. But in fact Chamberlain's efforts ended in failure. If Hitler had wanted war on 1 October 1938, he could have had it. The French and British had reached the point at which they could make no further concessions. The armies of France and the Soviet Union had mobilized. The Royal Navy stood at full alert. On 29 September 1938 it was Hitler who stepped back not his opponents, and there is no better explanation for this abrupt change of course than the sheer weight of evidence, argument and pressure that had been brought to bear on him over the previous weeks. Hitler was hearing expressions of concern not only from Beck and Krosigk, but also from Goering and most importantly perhaps from Mussolini, who intervened personally on 28 September. Nobody could accuse either Goering or Mussolini of opposing war on principle. But neither wanted to risk a war against Britain and France in 1938. Furthermore, if Hitler abstained from open military aggression, the British and French were clearly willing to give him virtually everything he might ask for. Reluctantly, Hitler backed down and accepted the extraordinarily generous settlement on offer at the hastily convened conference in Munich. In so doing, he almost certainly saved his regime from disaster."
- Wages of Destruction by Adam Tooze

Propaganda puts Chamberlain as spineless, the reality was that he was not. Britain and its empire was not attacked or attacked anyone. He declared war on Germany out of principle.

"The Anglo-American Trade Agreement signed on 2 November 1938 sent a clear message to Berlin. As Britain and America celebrated their new unity of purpose, Goebbels issued strict instructions banning the German press from any comment implying that Berlin viewed the agreement as a significant 'victory for democracy’. Chamberlain was particularly pleased by intelligence reports, which suggested that the Germans believed that the agreement included ’secret military clauses’. In fact, it contained no such thing."
- Wages of Destruction by Adam Tooze

Britain and France had not armed as fast as Germany needing to catch up quickly. The depression hit idle industry of the USA was available to catch up. Churchill regarded the industry of the British empire and the USA as all one, as he had open access to all of it.

"Britain had taken the unprecedented step of issuing a public guarantee of Poland's territorial integrity. To give this promise substance, Britain and France opened negotiations with the Soviet Union over the possibility of concluding a security agreement that would protect the rest of Eastern Europe against any further German aggression. With hindsight it is clear that these negotiations were doomed to failure. Ironically, a guarantee to the Poles made a deal with the Soviets impossible. However, in the spring of 1939 the formation of a triple alliance of France, Britain and the Soviet Union against Hitler seemed inevitable. The British cabinet, despite the reservations of Chamberlain, was genuinely committed to seeking a Soviet deal. And though the replacement of Maxim Litvinov as Soviet Foreign Minister was disturbing, Stalin and his new Foreign Minister Vyacheslav Molotov certainly took the possibility of a Western deal seriously."
- Wages of Destruction by Adam Tooze

It was Chamberlain who scuppered the British-Franco-Soviet alliance, with his anti-Communist feelings getting the better of common sense. If the triple alliance was formed Hitler would not have attacked anyone.