They made this to preserve and protect themselves from the wars in the world. President Woodrow Wilson motivated the Americans to stay neutral as it is called safe democracy. He decided not to let Americans get involved in the wars of other nations. He also stopped providing military assistance to show his neutrality.
The answer should be the first given “These weapons of mads destruction are capable of killing thousands of people in one attack.”
Germany ending the war is an armistice, as an armistice is a temporary call for peace.
