No US entry into WWI, what happens?

Apart from Russia, which ones, why and when?
Russia may fall earlier then OTL. Because they lack the USA entry to keep them in for a time.
Italy may or may not feel that they have to get out after Capporetto. Maybe the Entente could hold them, but at what cost?
France, had OTL the problems with its army, solved in part because USA troops would arrive in time. Here no such boost to morale has happend / will happen. So they will be weaker then OTL.
And lst but not least Britian will have to sell its beggers bowl... so they may find their imports, and those of the whole Entente, cut to some degree.

So not only the CP was crumbeling but here the Entente will also face compunding hardships that can very well shake then appart.
 
That's going to happen anyways when the war ends, even if the US keeps loaning. In fact it would be worse as the US production keeps expanding. Early 1917 it will be a recession, possibly the worst of the 20th century so far, but much milder than post WWI OTL. Plus orders are going to peter off, rather than suddenly stop

Particularly if Britain decides to reserve her remaining funds to meet her own needs rather than subsidising her allies. So her purchasing may not stop right away.



They were almost certain A-H and the Ottomans were about to collapse in 1914, 1915, 1916, 1917...

That was the old "knock away the props" fallacy. In reality it was Germany who propped her allies up, not vice versa. Thus in the "Hundred Days", when Germany (losing nearly 4,000 men per day as prisoners or deserters) was under too heavy pressure to spare any forces, the CPs went down like ninepins, all falling in the space of six weeks and the last three all in the same fortnight.
 
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