IF the US Never Demobilized After WW1 and Kept an Army Base in Germany Would

[Winner]

Ah yes, the "Dolchstoßlegende". We have dismissed that claim.
(...)
This isn't really a Main Area of Disagreement, it's just that I noticed this rather pervasive and unfortunate myth come up in your argument and wanted to address it.

Be careful about dismissing claims, they might come to Earth in giant cuttlefish-like starships to bite you in the butt

Anyway, there was no need to actually tell me this, I only wanted to contrast the WW1 situation with the WW2 one. When Germany surrendered in May 1945, it was totally beaten, most of its territory was already under occupation, the cities were bombed to rubble, and its armed forces were all but crushed. Germany was far from that when it asked for an armistice in 1918.

I disagree. I think that the Allies would have lost the war in the fall of 1917, if not earlier, if the United States had remained neutral. The reasoning is fairly simple, actually.

My assumption was that the US would have kept bankrolling the Allies without actually joining in the war. How realistic that would have be is open to debate, personally I don't think the Americans would have wanted the Entente to collapse and lose, so the tap would have remained open. I just wanted to dispel the myth that the American troops somehow brought about a swift victory over Germany.

What happens if the British economy tanks? Well, for one thing, the armies on the Western Front run out of steam. Haig's grand offensives to take pressure off the French don't happen. If the Nivelle Offensive still occurs, it would almost certainly fail quite badly; if the mutiny still happens, which is probable, it would be deepened by Britain's (and France's, indirectly) economic woes. Would that be enough to permit the Germans to take advantage with their own offensives? Probably. Imagine the sweeping attacks into Germany in 1945, with the Wehrmacht utterly starved of resources, lacking fuel for its tanks, food for its soldiers (and its people!)...German troops surrendered in droves. What would prevent the same from happening in Flanders, if the British were down to shrinking stockpiles of ammunition and supplies?

Maybe the fact that the Germans weren't much better off at this point?

And what about the specter of social revolution at home? Perhaps it would not be enough to actually start such a thing, but the fear of it could bring Lloyd George to the negotiating table...combine it with the collapses in Italy and Russia, and the Central Powers would be victorious on practically every front.

Now, I agree with you that if the Americans had stopped assisting the Entente entirely, the prospect of CP victory would have improved. On the other hand, it would hardly be a crushing victory. France would have asked for an armistice, the Germans would have screwed it over just like the French screwed them over in OTL, the Brits would probably disassociate themselves from Europe and focus on holding their empire together and... I don't know. I am in the middle of a Kaiserreich game right now, so I am going to finish it (by nuking the hell out of the Combined Syndicates of America) rather than speculate here

Like you, I'm a little dubious about American contributions to the actual fighting, and whether they were, strictly speaking, completely necessary to the victory over Germany. Since the Germans screwed up their own offensive (which on its own had quite a good chance of destroying the British army on the Continent), it's difficult to envision a scenario in which the Germans could have pulled their attack off after about May or so. I think that, less American manpower, which did plug some rather important holes and which did conduct some rather difficult operations in the post-"Black Day" offensives, the British and French would certainly have felt a bit of a squeeze. They still would probably have avoided losing the war in 1918, but I'm not sure that the French, at least, could have launched offensives without the Americans present to relieve pressure and attack the Germans of their own accord. There would be no "Hundred Days", to say the least, and the war might very well have stretched into 1919. Hard to say. But yes, America's military contribution was not nearly as important as the financial one.

And this is what I had in mind.