United states enter world war 2 1940

What if the united states enter world war two in late 1940 .pod a uboat sinks a united states warship with not survivors.does germany invade Russia ?
 
No.

Out of sheer necessity, Hitler will try to upgrade the non-aggression pact with the Soviet Union into a true alliance, as Stalin actually wanted. Concessions would obviously have to be made to the Soviets, especially in the Balkans, but in the end, the two powers would come to an agreement.
 
Probably. Hitler worried so little about the US that HE declared war after Pearl Harbor. I don't see him changing plans as a result of this.

The only change might be that in 1941 he thought that the US would be too occupied against the Japanese to do anything in Europe. ITTL, if the US is declaring war first on Germany, that might not happen. I imagine Hitler will try to placate the Americans, and if he tries to appear "genuinely sorry" and if the diplomatic wrangling lasts long enough it may result in Congress refusing to declare war.
 
Industrial mobilization of the US is accelerated a year or two. Until the DoW & accompanying War Acts legislated the US was still under peacetime economy 1940-41. This seriously hampered industrial mobilization. So a DoW in 1940 means the US reaches its material productions levels of 1944 OTL a full year or more earlier.

With earlier full on participation of the USN the Battle of the Atlantic is won near two years earlier. The Germans can still win some tactical victories at sea, but they won't cause near the levels of damage as OTL.

While the US ground forces will be very small in 1940, mobilization to the levels of late 1943 or 1944 will be possible by late 1942.

Clearly there are huge strategic changes with the US participating from 1940.
 

McPherson

Banned
Hmm. The Tizard mission brings far less to the table as the British have not worked out a lot of the kinks in the gifts they bring to the US. OTOH Japan would be foolish to jump off against a mobilized US that has a year of war under her belt. Might have interesting effects on radar and torpedoes from my viewpoint. I'm not sure the European War gets much help unless Hitler goofs and makes it an EARLY January 1940 boob move.

With regards to Britain's efforts, there is nothing aside from a few obsolete tanks and a few unready prototype planes the US brings to the table. The timeline ATL still will be 1942 before serious equipment transfer in a meaningful and useful way happens. Now if the Berlin maniac really boobs and the SS Calvin Coolidge is sunk a la Lusitania in October of 1939, things can get very exciting and interesting for the Germans in a real hurry. It may take 6 months but France 1940 looks a lot different.
 
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Not necessarily. The U.S declares war by say a slight majority in Congress in February 1940 over a U-Boat sinking a ship in the Atlantic it will be pulling teeth to get near the kind of total mobilization of society and level of public sacrifice seen in the U.S. after Pearl Harbor when the public mood was very different and the political class was highly united about the need for a total mobilization of American society to win an existential two front war.

...

If there is not the level of support then a DoW is not going to occur. The legislation that accompanied the DoW in December 1941 enabled the Executive branch to rationalize priorities for materials allocations, and alter the peace time system for allocation of Dept of War & Dept of Navy contracts. I suspect the sort of national mobilization you are thinking of was that achieved in 1944. That certainly was not reached in 1942 & that level of effort would not even be desirable in 1940-41. Unless there is some sort of much earlier change in US war planning There will necessarily be a spin up period before its desirable or practical to reach the OTL production levels & effort of 1944, or even 1942-43. OTL it took from October 1940 to mid 1941 to expand the US Army from 230,000 to 1,600,000. So its going to be some time before full blown total war economy is necessary. Kleins 'A Call to Arms' has a 897 page primer on the US industrial mobilization. He touches on things like the errors made in the Great War industrial mobilization, and the false starts of 1938-1941.

Think of the frog boiling metaphor. Industrial mobilization accompanying a 1940 DoW will be more effective than the crippled pre 1942 attempts of OTL, but a lighter touch than the full court press of 1943-44.
 
Think of the frog boiling metaphor. Industrial mobilization accompanying a 1940 DoW will be more effective than the crippled pre 1942 attempts of OTL, but a lighter touch than the full court press of 1943-44.

I would agree with that. But, I am not sure how well you get to the full court press part if the war starts early over a u-boat sinking which had been my point.

The biggest change of American entering the war in 1940 on the German side would be much more institutional military reluctance to open up a second front in 1941.
 
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Indeed, there are significant differences between the two dates. In December the collapse of France is a done deal. In january the world is full of possibilities.
 

thaddeus

Donor
Indeed, there are significant differences between the two dates. In December the collapse of France is a done deal. In january the world is full of possibilities.

how do you think it would affect the Vichy regime, if the US entered the war in 1940, until the OP is clarified just say during last quarter of the year?

and if things are heating up between Germany-US, do you think Germany might put more importance on striking an agreement with France over catering to Japan in Indochina?
 
and if things are heating up between Germany-US, do you think Germany might put more importance on striking an agreement with France over catering to Japan in Indochina?

When Rommel advised Hitler to go for a full peace with France when he got back Hitler said he worried about the Italians and their North Africa claims. I am sure Japan was a factor as well.

Still if the U.S is in the war in early 1940 it changes the calculation of a lot of actors. Namely Berlin wouldn’t believe holding NA with some German troops to aid the Italian Army was a option if the Americans could just land on the other side of their forces trapping the force into an unwinnable two front war.

If the Germans decide NA is a loser and don’t commit then yes a full peace with Vichy could happen. At the same time Churchill is going to play it more conservatively if America is in the war earlier. I think he waits on his Balkans expedition and focuses on NA.

He probably doesn’t try a soft underbelly strategy until U.S. troops are ready to come along.
 
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Germany loses a major source of aluminum, American companies or shipping it to Germany through Spain. That will hurt aircraft production compounded by the fact American fighter squadrons both show up in the European theater of operations. One or two squadrons of P-40s during the Battle of Britain would make a difference.
 
Again, this all depends on exactly when the US enters the war. Examples:
-if the US enters in summer then American fighters showing up in Britain means a shorter BoB with the Germans getting a bigger bloody nose and the USAAC getting earlier combat experience.
-if the US enters earlier enough before May then there may be no Vichy and Italy may think twice before declaring war at all. That means the Med. stays an Allied lake.
 
how do you think it would affect the Vichy regime, if the US entered the war in 1940, until the OP is clarified just say during last quarter of the year?

Pertains government has less collaborationist character. Retains long term goal was to restore the former power of France and its independence. One of the reasons why he initially expected a peace treaty to be negotiated in the winter of 1940-41. The collaboration policy and Laval taking the prime ministry reflected a deviational route & the view that Britain could not win. If the US enters as a active partner Petain is much less likely to support laval & the collaborationists. Darlan & other will also steer awards a stricter neutrality. The Germanophobes will be even less cooperative & think and plan for resistance to German policy.

...and if things are heating up between Germany-US, do you think Germany might put more importance on striking an agreement with France over catering to Japan in Indochina?

Possibly. One of the motivators in the agreement to allow the Japanese occupation of FIC was the belief that France could not defend the place from Britain. Better to abrogate the Armistice agreement in this case than allow some future British seizure. A revolt there in favor of the Free French was another scenario. But if Germany if seriously negotiating a peace treaty with France then violating the Armistice makes less sense.

I guess in all this the question of peace with Britain is the pivot. OTL Hitler postponed a peace treaty with France as he & Ribbentrop wanted to concoct some sort of grand structure for all of western Europe. With Britain and others like Norway, Netherlands, ect... holding out negotiations with France were tabled indefinitely.

When Rommel advised Hitler to go for a full peace with France when he got back Hitler said he worried about the Italians and their North Africa claims. I am sure Japan was a factor as well.

Still if the U.S is in the war in early 1940 it changes the calculation of a lot of actors. Namely Berlin wouldn’t believe holding NA with some German troops to aid the Italian Army was a option if the Americans could just land on the other side of their forces trapping the force into an unwinnable two front war. ...

OTL the decision to actively support Italy in the Med did not come until March 1941. The Yugoslavian takeover by a pro British government was a important factor in this. With the US active in 1941 there is a larger possibility German soldiers are not sent to Africa. With USN assistance the Italian position in Lybia looks far worse & irretrievable.
 

nbcman

Donor
We're much more likely to see BoB 2.0 in 1941 than Operation Barbarossa.
Why? BoB 1940 was done to prepare the path for Sealion. With the combined strength of the RN and the USN, Sealion is now completely impossible in the almost impossible event that Luftwaffe could defeat both the RAF and the USAAF in 1941.
 
Hm, if the Americans join early enough, that probably stops Churchill pushing the Mers-el-Kebir attack, which means the Vichy Government is more friendly.
 
Why? BoB 1940 was done to prepare the path for Sealion. With the combined strength of the RN and the USN, Sealion is now completely impossible in the almost impossible event that Luftwaffe could defeat both the RAF and the USAAF in 1941.

Let's say that Germany decides in early 1941 to go with Op Barbarossa despite the USA entering the ww2 in 1940.
They need to deal with Yugoslavia and Greece, help Italians not to loose in Libia, defeat Soviet Union, keep a knife under Vichy's throat so those don't chage sides, keep a sizable garrison from north of Norway down to Spanish border, all while avoiding not to be defeated by RAF and USAAF in mid-1940. Quite a tall order, don't you think?
 
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