Absolutely. In many ways WWI was actually more important, historically speaking, than WWII. In destroying the Empires, creating the new power centers of Soviet Communism and US-style capitalism, and fatally undermining the French and British Empires it created the trends WWII simply confirmed. Taking into account the degree to which the grinding battles of the Eastern Front of WWI in particular created the modern world, I've always been puzzled at the degree to which that part of WWI has been neglected. It if anything was more decisive than its WWII equivalent.

And the psychological trauma factor proved immensely greater for everyone involved in WWII.