“World War II was inevitable”

Question

inevitable: Impossible to avoid or prevent

Why is this statement true?

To understand this, you have to understand WWI and its aftermath -- and why many Germans were terribly frustrated and angry.

http://en.wikipedia.org/wiki/Aftermath_of_World_War_I

http://www.infoplease.com/ce6/history/A0862008.html

http://en.wikipedia.org/wiki/World_War_II
Scroll down to the section called Causes.