John Green teaches you about the war that was supposed to end all wars. Instead, it solved nothing and set the stage for the world to be back at war just a couple of decades later. As an added bonus, World War I changed the way people look at the world, and normalized cynicism and irony. John will teach you how the assassination of an Austrian Archduke kicked off a new kind of war that involved more nations and more people than any war that came before. New technology like machine guns, airplanes, tanks, and poison gas made the killing more efficient than ever. Trench warfare and modern weapons led to battles in which tens of thousands of soldiers were killed in a day, with no ground gained for either side. World War I washed away the last vestiges of 19th century Romanticism and paved the way for the 20th century modernism that we all know and find to be cold and off-putting. While there may not be much upside to WWI, at least it inspired George M. Cohan to write the awesome song, "Over There." [11:44]