On April 6, 1917, the United States declared war on Germany and joined World War I. German submarine attacks on American ships in March 1917 were the overt motive for declaring war, but the underlying reasons were far more complex. Even after the United States officially joined, Americans were divided on whether they should be a part of it. Americans were told they were fighting a war for democracy, but with racial segregation rampant in the United States, new laws against dissent and espionage being passed, and bankers and industrial leaders gaining increased influence and power, what did democracy mean? Come On In, America explores not only how and why the United States joined World War I, but also the events—at home and overseas—that changed the course of American history.