Okay, so obviously nuclear weapons proved to be a threat that would possibly destroy the world. The Soviet Union and the United States build up a stockpile of nuclear weapons and used the fact that the world may be destroyed to keep the other country at bay.
WOW!? That's a lot of questions....:(
World War I
World War I lasted from July 28, 1914 – November 11, 1918. It started when the Archduke of Austria-Hungary, Franz Ferdinand, was assassinated by Serbia. It ended when Germany formally surrendered.
Fort Sumter. April 12, 1861
They wanted shorter working days (such as 8 hour days for example)