I’d say it’s a lot more complicated than that. You can’t lay all the blame on Wilhelm II. He was a major player of course, but there were quite a few trigger points at which individuals could have stopped the war, and he was just one of those individuals. Now you can make a case that he was a strong contributor to the powder keg that was waiting (with his provocative positions such as his naval race with the UK), but the rulers of Serbia, Austria, or Russia could have stopped the war from occurring as well.
The rulers of Serbia were as “compliant” as humanly possible (more than they should have been) to Austria’s “Ultimatum” of July 23, 1914, and it still wasn’t “good enough”. Nothing that Serbia did or did not do would have prevented Austria from attacking her, because Austria was hell bent on crushing Serbia.
Well, she should have rethought that desire, because in the end, it was the Austro-Hungarian Empire that was “crushed” and dissolved.
Wilhelm II is a bit of a complicated case. While on the one hand he was pushing for war, on the other, when war was actually becoming a very real possibility, he started backtracking. By that time though, the wrecking ball was not to be stopped.
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