- World War I 15-19 million deaths.
2. World War II 70-85 million deaths
World War III deaths are yet to be determined, but it is sure to be worse. It is worthwhile to point out, however, if the US had not gone into isolation and boycotted the League of Nations after the first war, maybe the second would have been averted.
Entirely possible. Had Clemenceau moderated his demands to bankrupt Germany via war reparations, had Germany’s economic regeneration not been derailed by hyper inflation, had not the Great Depression paved the way for Hitler (who otherwise might have been a dismal footnote) just maybe WWII might have been avoided. BTW, I’m reading a book you might enjoy (via Kindle): Dance Between Flames: Berlin between the Wars, by Anton Gill. It is sort of a social history of the period. There’re some disturbing parallels with today’s Life Under Trump.
Of course, without Hitler would we still have had to face a Greater Co-Prosperity Sphere under Japan?