Oh, sure, he doesn't deserve all of the blame. But the brutal murders he perpetrated were the instigating event for almost all of 20th century history. Without WWI there'd have been no WWII, no Communist revolutions, no Cold War, no Korea, no Vietnam, no Holocaust — it's unknowable what an alternate history of the 20th century would look like, because the Great War completely and utterly shattered Western civilisation.

Yeah, he was a tool of others. But he was the one who pulled the trigger: the spark that ignited in the primer of his pistol cartridge is still burning.