The war was so big that if each citizen had not done his bit, Germany might have conquered. The work of shipping boards and directors of fuel supply was less important than the work done by ordinary people. Much was done to win the war in the homes of each boy and girl in the United States as well as on the battlefields of France. Every member of the family found things he could do without to help buy more Liberty bonds. Boy Scouts sold bonds and thrift stamps. Girls worked to get food-card pledges. Mothers planned the meals carefully to save the wheat, meat, and sugar that had to be sent across to our army. Brothers and fathers had to answer the draft call and go to training camps if necessary. Not only must food and money, gasoline and coal, be saved, but everyone who could not fight overseas was expected to do some useful work. [Illustration: A WAR GARDEN POSTER _In the "Food Will Win the War" campaign posters urged all school children to make gardens_] With one hundred million people in the country, we might think it would not make any difference if we let someone else do our part. But this was not the spirit of America. For the most part, each person himself felt that this was _his_ war, fought for _his_ rights and for _his_ aims. And because for the most part each person acted as if success depended on him, Europe was amazed at America's swiftness in getting ready to fight. [Sidenote: =America by tradition aloof=] The United States did not decide to enter this war until it had been going on nearly three years, for its people had come from nations fighting on opposite sides. Besides, war had always been a common happening in Europe, and the United States had always tried to keep its hands free. Washington and Jefferson and later Monroe had advised that we should only be "interested spectators" of quarrels abroad. [Sidenote: =The powers involved=] =233. A World at Arms.= The outbreak of the war surprised the world by its suddenness. The heir to the throne of Austria, Archduke Ferdinand, was murdered in June, 1914. Austria blamed Serbia for the murder. When Serbia would not agree to all that was demanded of her, Austria at once declared war. The largest nations of Europe were united in two groups. Germany took up Austria's quarrel; Russia, France, and England combined to oppose Germany. Italy was bound to defend Germany and Austria if they should be attacked, but now believed they were the attacking nations, and later came in against them. Bulgaria and Turkey threw in their lot with Germany and Austria, these four nations forming the Central Powers, and Japan and Roumania with the Allies, as the nations opposing them were called. [Sidenote: =Invasion of Belgium=]