Write short essay for this question:
Historians sometimes present World War I and World War II together as a second "Thirty Years War." So discuss the relation between the two - what are the reasons for seeing the conflicts as a single episode in global history? How do you account for the long pause in between the two cycles of warfare? What is the upshot of seeing WWI and WWII as a single vast struggle - what had changed, at the global level, between 1914 and 1939?