I guess you forgot about the Conscription Crisis of 1917.

https://en.wikipedia.org/wiki/Conscription_Crisis_of_1917

https://fr.wikipedia.org/wiki/Crise_de_la_conscription_(1917)

WW1 was a clash of empires established by violence and advanced military technology over less developed countries, not a clash between good and evil. It demonstrated the unfortunate truth of this advice: 

''In 1882 I was in Vienna, where I met an American whom I had known in the States. He said: 'Hang your chemistry and electricity! If you want to make a pile of money, invent something that will enable these Europeans to cut each others' throats with greater facility.' ''

http://www.nytimes.com/1985/11/26/science/100-years-of-maxim-s-killing-machine.html

https://en.wikipedia.org/wiki/Hiram_Maxim