What is the difference between aid, a treaty, and an alliance?
An Aid assists or helps during war to help win the war, but an Treaty is an agreement between two countries, so in a treaty they don't help each other, just agree on something. An alliance is a benefiting relationships between two or more countries when they have common interest or goal.
Why isn't the United States a part of the diagram above?
United States did not take part in World War 1 until April 6, 1917, when World War 1 started July 28, 1914.
Does the United States become a part of the diagram? If so,
when and why?
Yes, when they join World War 1 in 1917, because they allied with Britain, France, and Russia.
An Aid assists or helps during war to help win the war, but an Treaty is an agreement between two countries, so in a treaty they don't help each other, just agree on something. An alliance is a benefiting relationships between two or more countries when they have common interest or goal.
Why isn't the United States a part of the diagram above?
United States did not take part in World War 1 until April 6, 1917, when World War 1 started July 28, 1914.
Does the United States become a part of the diagram? If so,
when and why?
Yes, when they join World War 1 in 1917, because they allied with Britain, France, and Russia.