Which one was more crucial and decisive: United States intervention in WWI, or WWII?

[Rex Romanum]

I've seen arguments from both sides on the Internet.

The first group argued that had the USA not entered the First World War on the Entente side, the Central Powers would've gained phyrric victory. OTOH, the Allies would still win the Second World War regardless of US intervention, since no way the Nazis can conquer either Great Britain or the USSR, while Japan would not be able to assimilate China.

The second group meanwhile argued that the Entente was simply superior economically than the Kaiserreich and thus if the USA didn't interfere the First World War would still ended with late Entente victory. Meanwhile the British and the Soviets would have surrendered to the Third Reich, and Japan forged an impressive Empire and/or Co-Prosperity Sphere in the Far East, if the USA had insisted to kept its neutrality throughout the Second World War.

What do the people of AH.com think about this?

 

[Perfidious Albion]

I'm not sure where the argument that the Entente would have defeated the Central Powers anyway comes from. Yes, the Germans were being blockaded and German civilians were starving to death, but much of the industrial heartland of France was under German occupation, significantly denting the effective power of that state, and the British were running out of money (specifically, possessions in the United States with which to make secured loans) to sustain their war effort. Once the millions of German soldiers start coming westward from the Eastern Front, without American aid it's hard to see how the Entente could have made it. Imperial Germany was exhausted, but as far as I know it wasn't reaching the point of imminent financial failure as the Entente powers were.

In the Second World War, on the other hand, Tube Alloys + lack of likelihood of British surender + lack of likelihood of Soviet surrender + lack of likelihood of German victory over the Soviet Union = very very unhappy Germany. This applies even if the USA keeps itself busy using FDR's lofty rhetoric of "fighting a war for democracy" (against his political oppponents, that is) while completely ignoring the various peoples acrosss the world who actually were fighting a war for democracy and bullying Latin American countries as usual. Contrary to anti-communist rhetoric, the Soviets only started receiving really large quantities of war materials from the United States after they'd already turned the tide against Germany; without American help they'd suffer more and take more casualties but they'd still win in the end, and the British would take much longer to set up an effective invasion of Europe than the OTL British + Americans did. After that, Imperial Japan, facing an unwinnable war in China, can't realistically hope to hold China against Chinese and Soviet opposition, especially given how vastly superior the late-WW2 Red Army was to the IJA (look at August Storm and it's as close as one gets to a real-life curb-stomp).

TL;DR: American non-participation in the First World War leads to a pyrrhic victory for Imperial Germany, whereas American non-participation in the Second World War just leads to a greater Soviet-wank in the division of the spoils post-war.

 

[BooNZ]

TL;DR: American non-participation in the First World War leads to a pyrrhic victory for Imperial Germany, whereas American non-participation in the Second World War just leads to a greater Soviet-wank in the division of the spoils post-war.

Britain was broke again by the end of 1940, so no lend-lease means Britain is out - no lend-lease would be reaching the Soviets either.

 

[Niko Malaka]

If by intervention you mean proper military intervention, there is no contest. American intercention in WWI pales compared to the numbers, the effort and the effects over the terrain of american intervention in WWII.

Now, if by intervetion you mean something more generic, then there is contest. Without the american credit, and the efforts made by the Wilson administration to keep the credit flowing towards the Entente, there is a high probablity that the alEntente would have been broke by 1918 and therefore defeated. On the other hand the lend-lease and again the american creditk Britain and the SU union afloat in WWII before the american direct involvement....

 

[Anaxagoras]

By 1917, the Allies would have won the First World War even without American help, albeit later and at greater cost.

 

[Deleted member 1487]

I said both were crucial, but with the caveat of WW2 being even more so.

 

[Deleted member 1487]

By 1917, the Allies would have won the First World War even without American help, albeit later and at greater cost.

No way in hell without US unsecured loans, which only happened due to US entry; even their 1918 success was largely based on the US allowing a more than 2:1 superiority in manpower in the frontlines, even just by taking over less active fronts to allow the British and French to concentrate their forces for the big offensives starting in August, but also their counteroffensives/reserves during the German offensives.

 

[Anaxagoras]

No way in hell without US unsecured loans, which only happened due to US entry; even their 1918 success was largely based on the US allowing a more than 2:1 superiority in manpower in the frontlines, even just by taking over less active fronts to allow the British and French to concentrate their forces for the big offensives starting in August, but also their counteroffensives/reserves during the German offensives.

I don't think the Allies could have won in 1918 as they did IOTL without American help, but I think the Allies would have held on until Germany collapsed at some point in 1919.

 

[Deleted member 1487]

I don't think the Allies could have won in 1918 as they did IOTL without American help, but I think the Allies would have held on until Germany collapsed at some point in 1919.

That's the thing, Germany was far better off and in fact economically improving after the disastrous winter of 1916-17, while France and Britain would experience economic collapse because of food shortages, lack of oil, US steel, and a few other things. France in particular was dependent on imported food because of the loss of agricultural land to Germany and the heavy mobilization for farmers for the war. France would collapse without US loans in 1917, while Britain could muddle on for a while. Italy would likely go down too, while Russia would have to tap about before the Kerensky offensive. The CPs can outlast the Entente economically because they had been forced to establish an independent economy without imports from 1914 on; but without the US in the war trickles of supplies can still be imported via the Netherlands, which IOTL was cut off by US entry. Also the British Blacklist that kept the blockade going would fall apart because of the lack of money to buy up excess international trade.

 

[machine3589]

American intervention was crucial for the outcome of both wars.

 

[Redbeard]

By April 1918 when the German spring offensive bogged down, the war was definitively lost for the Central Powers. USA played no significant role in stopping the offensive. US troops were significant in the Entente summer and autumn offensive of 1918 however with more than a million men in the field and even if Pres. Wilson advocated for tolerance towards a defeated Germany the humiliation of Germany at Versailles probably wouldn't have been possible without the massive US involvement from summer of 1918.

So without US in WWI the Entente probably would have won anyway, but not have been able to force quite so humiliating terms on Germany.

USA not intervening in WWII does not necessarily mean no lend-lease or other arrangements to keep the Brits in the fight, but the Brits alone will not be able to seriously intervene in NW Europe like in OTL - D-day or bombing offensive.

The extra resources freed for the German effort on the Eastern Front might not have them defeat the USSR but OTOH I doubt the Soviets will be able to advance into German territory. IOW Nazi Germany will still be standing in some form.

All in all: No US intervention in WWI - no nazis, but OTOH the US intervention in WWII was significant in removing the nazis again, which is more crucial and decisive is hard to say, but I'll say the WWII one as the WWI as the effects were unintentional whereas the WWII one actually achieved was intended.

 

[Deleted member 1487]

By April 1918 when the German spring offensive bogged down, the war was definitively lost for the Central Powers. USA played no significant role in stopping the offensive. US troops were significant in the Entente summer and autumn offensive of 1918 however with more than a million men in the field and even if Pres. Wilson advocated for tolerance towards a defeated Germany the humiliation of Germany at Versailles probably wouldn't have been possible without the massive US involvement from summer of 1918.

So without US in WWI the Entente probably would have won anyway, but not have been able to force quite so humiliating terms on Germany.

USA not intervening in WWII does not necessarily mean no lend-lease or other arrangements to keep the Brits in the fight, but the Brits alone will not be able to seriously intervene in NW Europe like in OTL - D-day or bombing offensive.

The extra resources freed for the German effort on the Eastern Front might not have them defeat the USSR but OTOH I doubt the Soviets will be able to advance into German territory. IOW Nazi Germany will still be standing in some form.

All in all: No US intervention in WWI - no nazis, but OTOH the US intervention in WWII was significant in removing the nazis again, which is more crucial and decisive is hard to say, but I'll say the WWII one as the WWI as the effects were unintentional whereas the WWII one actually achieved was intended.

Nonsense the US had 4 divisions, each equivalent to a Entente corps in size, in the line in quite sectors during the German offensives and that freed up a lot of French troops for operations at a critical moment. That's also ignoring the huge food, oil, and steel contributions that were made by the US and was paid for by US loans that enabled the Entente to continue the war past 1917. Without that the Entente would have collapsed economically.

 

[Mikestone8]

By April 1918 when the German spring offensive bogged down, the war was definitively lost for the Central Powers. USA played no significant role in stopping the offensive. US troops were significant in the Entente summer and autumn offensive of 1918

Except that the Entente is having to do without the billions of dollars they got in unsecured loans, and all the war material purchased with them.

Given how closr-run the battles of March-April 1918 were, it's more than likely that their outcome is reversed, even if Ludendorff (who is no longer "running against the clock" doesn't take more time to plan the offensives better.

 

[Aber]

Nonsense the US had 4 divisions, each equivalent to a Entente corps in size, in the line in quite sectors during the German offensives and that freed up a lot of French troops for operations at a critical moment.

Would you like to guess the total number of British French and Belgian divisions on the Western front?

 

[Deleted member 1487]

Would you like to guess the total number of British French and Belgian divisions on the Western front?

How much difference did 4 corps worth of French infantry make to their ability to hold come May 1918? A lot in fact, as that is the better part of an entire army.
https://en.wikipedia.org/wiki/Third_Battle_of_the_Aisne
https://en.wikipedia.org/wiki/Second_Battle_of_the_Marne
Come the 2nd Marne there were 8 US divisions, equivalent to 8 French corps in size, participating in the battle in addition to the divisions on other fronts freeing up even more French divisions for the battle.

 

[matzeskatze]

Let's not forget the French morale that was, lets say, shaky at some points in 1917. Imo the USA entry did much to stabelize that and also give fresh wind to the British.

Would that still have happened if the USA stayed out? Imo the loss of Russia will sap strength longer and may compound earlier problems.

 

[Indicus]

In WWI, while Germany was close to collapse in 1917, the Allies were being beaten back and the Germans were moving towards Paris. I think if the US never intervened, Germany would win the war and sign a peace and then would face instability caused by the SPD. I don't know who would prevail, but Germany would win the war and lose the peace in such a scenario.

If the US never intervened in WWII, the Soviets would beat back the Nazis and would probably reach Paris before the end of the war. This is better than a Nazi victory scenario, but not a very utopian one either.

I think the US was more crucial in saving Europeans from totalitarianism in WWII, but in the strictest sense of the was more crucial in WWI.

 

[King Augeas]

Britain was broke again by the end of 1940, so no lend-lease means Britain is out - no lend-lease would be reaching the Soviets either.

If no lend-lease also means no repeal of the Neutrality Acts, then Britain isn't dollar-broke because it isn't spending dollars on US weapons. And most of the rest of the world accepts sterling.

 

[Kaiser K]

WWI by a wide margin, the Entente was in near economic ruin by 1917 and would not have lasted without the unsecured loans or war materials that they got from the Wilson administration after the U.S.'s entry into the war.

 

[cra0422]

I think that both were important, but I also wonder if the US hadn't intervened in WWI how might have Germany's position at the negotiating table have changed, and if Germany hadn't essentially gotten screwed by the Treaty of Versailles, would the Nazis have come to power forcing WWII?