Capitalism? What? Fascism has nothing to do with that. Ideas are entirely responsible for fascism. Material conditions? I don't know what the fuck you're talking about. Fascism wouldn't have existed if Hitler either died as a baby or hadn't written Mein Kampf.
Oh, and, by the way, WWI could have been averted if that archduke didn't get shot. There is nothing more to the outbreak of WWI.
Sincerely, libs.
WW1 was just a holiday dinner bruh moment between incestual royal families that got milliions killed.