Dulce et Decorum Est
Jon Chait had a funny column over the weekend comparing the '06 midterms to World War One. At the very end, though, it offers up some fairly odd commentary on the war itself: "Woodrow Wilson didn't make the world safe for democracy, but he did manage to keep a pretty noxious regime from dominating a continent."
Wilhelmine Germany wasn't especially noxious. It was quasi-democratic and evolving in the direction of greater democracy. Among its opponents was Tsarist Russia, the most noxious regime on the European continent at the time. And, of course, the allied victory didn't exactly prevent noxious Germany from dominating Europe . . . the Germans came back, in much more noxious form, and tried again. Even though Nazism only lasted 1933-1945 it inflicted sufficient suffering that I think it's extremely plausible that the world would have been better off with a German victory. The real twist, however, is what would have been the fate of the Bolshevism in case of a German win. It would depend, I suppose, on how and why the German victory was achieved.
On top of that, reliable sources have contended to me that American intervention in the war wasn't especially decisive, though I'm not sure about that one way or the other.