By the early 1900's , the United States was one of the richest nations in the world. Every year thousands of ships left ports like New York and New Orleans loaded with steel, machinery, and other goods. They sailed to other countries in all parts of the world. Americans were also starting businesses in other countries.
As trade and industry grew overseas, the United States found itself more involved in events in distant lands. Americans liked taking a leading role in world affairs. However, they did not like the thought that they might be dragged into quarrels in other parts of the world. That concern grew in 1914.
On a Sunday afternoon in June, two young students from the small country of Serbia in Eastern Europe shot and killed the nephew of the Emperor of Austria. When Americans read of the event on Monday morning, few dreamed it would lead to a world war. Yet within a few years, 30 countries were drawn into a world war including the United States.