Aid is when a country gives supplies to another country but doesnt help fight. A treaty is to give peace between nations. An alliance is when countries come together in or before war to fight together for the same cause.
The United States isn't part of the diagram because they had no reason to fight they were not the Allied power at that point. But when Germany sunk the Lusitania in 1915 and two years later they joined the war.
The United States isn't part of the diagram because they had no reason to fight they were not the Allied power at that point. But when Germany sunk the Lusitania in 1915 and two years later they joined the war.