Like most of us, my history classes spent maybe one day on WWI and a week on WWII. During the last 10 years, I've really become fascinated with The Great War.
I agree 100% - World War I had a much larger impact on on world history than World War II:
I shifted the center of global economic power from London to New York
The collapse of the Ottoman Empire removed the stabilizing force in much of Eastern Europe and the Middle East
Catalyzed the Russian revolution and victory for the bolsheviks and led ultimately to the USSR, Cold War, etc. (Germans sent Lenin back to Russia in a train with the aim of destabilizing the empire)
Cemented a Anglo-Franco alliance after centuries of war and rivalry
Collapse or the Austro-Hungarian empire removed the stabilizing force in Eastern Europe and launched balkanization
The re-drawing of the geographic maps in the Central Powers can be viewed as the start of both WWII and 9/11
And it is amazing that the war began on bicycles and horseback with soldiers dressed in 19th Century colorful uniforms and ended with massive slaughter in trenches from airplanes, machine guns, and long-range artillery.