Why World War I and World War II are really the same thing

We can agree that two wars are different only when they are fought by different countries over different things, and I posit that World War II, which was fought by substantially the same countries as World War I, was also fought over the same thing:  whether or not German nationalism could take over the world.

Apparently some people disagree with me (this guy mentioned something to that effect), i.e. those who put it that World War II was a referendum on fascism.  To this I say:  Fascism is first and foremost nationalistic, so we're not entirely in disagreement.  All of fascism's tenets--the individual's personal subjection in the face of the state, the all-powerful centralized government, the cult of the mass spectacle and the strong man, and even the comfortable things like free education--are nationalist in nature.  So, just as I posit that World War I came about almost entirely because of German nationalism, I posit that World War II broke loose under the strain of German (but also Italian) nationalism.