When World War I ended in 1918, the last thing people wanted was an even greater conflict. So why did the world return to combat just two decades later to fight World War II?
Granted, Germany’s invasion of Poland in 1939 triggered declarations of war from France and the United Kingdom, formally starting World War II. But that event was only the final straw in a series of events. Various other economic and political challenges had been building up tension for years.